The Bloomer Shorts Set Tutorial (Pt 1): Everything You Need to Know Before You Sew

If you’ve been scrolling through sewing feeds lately, chances are you’ve stumbled across the cutest little bloomer shorts sets and immediately thought, “I need to make that.” You’re not alone. Bloomer shorts have made a serious comeback, and for good reason — they’re comfortable, adorable, versatile, and surprisingly satisfying to sew. Whether you’re making them for a baby, a toddler, or even a child, this tutorial series is going to walk you through everything from start to finish.

This is Part 1, which means we’re laying the groundwork. Before a single stitch is sewn, there’s a lot worth knowing about fabric selection, notions, sizing, pattern preparation, and the little decisions that separate a project that turns out beautifully from one that ends up buried in the UFO pile. So grab your coffee, open your notes app, and let’s get into it.

What Are Bloomer Shorts, Exactly?

If you’re new to the style, bloomer shorts are gathered, puffed shorts with elastic at the waistband and legs. They have a full, rounded silhouette that gives them that signature cloud-like look. The name comes from the original bloomers worn in the 19th century as early women’s reform clothing, but today’s version is very much a children’s fashion staple — and honestly, one of the most charming garments in the sewing world.

They typically pair with a matching top, which is why this is called a “set” tutorial. In Part 1, we’re focusing on preparation and the shorts. Part 2 will cover the coordinating top and finishing the set as a complete outfit. But don’t skip ahead — the prep work here sets you up for success throughout the whole project.

Why Sew a Bloomer Shorts Set?

Before we dive into the technical details, let’s talk about why this project is worth your time.

First, it’s beginner-friendly. While there are a few techniques that might be new to you (like creating a proper casing or gathering fabric evenly), none of them are advanced. If you’ve sewn a few simple projects before — a pillowcase, a tote bag, maybe a simple skirt — you have everything you need to tackle bloomer shorts.

Second, it’s a fast sew. Most people can cut and sew a pair of bloomer shorts in an afternoon. If you’re sewing a set that includes a top, plan for a full day, but even that feels manageable and rewarding.

Third, the results are genuinely beautiful. Handmade bloomer sets photograph wonderfully, make incredible gifts, and have that handcrafted quality that you simply cannot buy at a big-box store. If you’re sewing for your own child, there’s something deeply satisfying about watching them wear something you made from scratch.

Fourth, the possibilities for fabric choices are endless. From quilting cotton prints to linen blends to Liberty of London florals, this pattern works with almost any light-to-medium weight fabric, which means you can tailor the look entirely to your taste.

Choosing Your Fabric

This is one of the most important decisions you’ll make for this project, so let’s spend some real time here.

Recommended Fabrics

Quilting cotton is the most popular choice for bloomer shorts sets, and for good reason. It’s widely available, comes in an almost overwhelming range of prints and solids, is easy to cut and sew, and holds its shape beautifully after washing. It presses well, which matters a lot for a project with multiple seams and casings. If you’re a beginner, start with quilting cotton.

Lightweight linen or a linen-cotton blend is another excellent option. It gives the bloomer shorts a slightly more elevated, natural aesthetic. Linen wrinkles easily, which some people love for the relaxed look it creates, but if you prefer a crisp finish, stick to a linen-cotton blend rather than pure linen. Note that linen can fray more than cotton, so finishing your seams becomes more important.

Chambray works beautifully for a more casual, everyday look. It’s lightweight, breathable, and has a nice drape that lends itself well to the gathered silhouette of bloomers.

Double gauze is a dreamy fabric for this project. It’s incredibly soft, has wonderful drape, and feels luxurious against a child’s skin. The only thing to know about double gauze is that it shifts while cutting and sewing, so you’ll want to use plenty of pins or clips and cut carefully.

Rayon challis is another option worth mentioning for slightly older children. It drapes beautifully and creates an incredibly fluid bloomer that looks almost ethereal. However, rayon is more slippery to work with, so it’s not the best choice if you’re just starting out.

What to avoid: stretchy knit fabrics don’t work well with this pattern, which is drafted for woven materials. Very heavy fabrics like canvas or denim will make the gathering stiff and won’t produce the soft, puffed silhouette that defines this style. Sheer fabrics like chiffon can work if you’re an experienced sewer and prepared to underline them, but they’re not beginner-friendly for this particular pattern.

How Much Fabric to Buy

Fabric requirements vary by size, but as a general guideline for a bloomer shorts set:

For sizes newborn through 12 months, plan for about 1 yard of fabric total for both pieces of the set, or ¾ yard if you’re making only the shorts.

For sizes 12 months through 3T, plan for 1.25 to 1.5 yards for the full set, or 1 yard for the shorts alone.

For sizes 3T through 5T, plan for 1.5 to 2 yards for the full set, or 1 to 1.25 yards for the shorts alone.

Always buy a little extra, especially if you’re working with a print that requires matching. An extra quarter yard can save you from a frustrating shortfall.

Fabric Preparation

Before you cut a single piece, wash and dry your fabric. This is not an optional step. Fabrics — especially cotton and linen — will shrink the first time they’re washed, and if you skip pre-washing, you’ll end up with a finished garment that’s suddenly too small after the first laundry cycle. Wash your fabric the same way you plan to wash the finished garment. If you’ll machine wash and tumble dry on medium heat, do that before cutting.

Once it’s washed and dried, press your fabric thoroughly. Cutting wrinkled fabric leads to pieces that are slightly off-grain, and being off-grain means your finished garment won’t hang the way it should.

Gathering Your Notions

“Notions” is the sewing world’s term for all the supplies beyond fabric that a project requires. For a bloomer shorts set, your list is refreshingly short.

Elastic is the most important notion for this project. You’ll need it for both the waistband casing and the leg casings. For the waistband, ¾-inch wide elastic is a comfortable standard for babies and toddlers. For the leg openings, ¼-inch to ⅜-inch wide elastic creates a gentle gather without being too tight around little legs. Make sure you’re buying proper knit or braided elastic, not the stiff woven kind — you want it to be soft and comfortable against skin.

Thread is another obvious but important choice. Use a high-quality, all-purpose polyester thread in a color that matches your fabric. Cheap thread breaks more easily and creates more tension issues. For a project this size, one spool is plenty.

Pins or sewing clips are essential for holding your pieces together while sewing. If you’re working with slippery fabric like double gauze or challis, more is always better.

A safety pin is invaluable for threading elastic through casings. Attach it to one end of your elastic, feed it through the casing opening, and use it to guide the elastic all the way around. This is one of those small tools that makes the process genuinely enjoyable instead of frustrating.

An iron and ironing board are non-negotiable for a professional-looking result. Pressing seams open or to the side, pressing fold lines for casings, and giving the finished garment a final press all make an enormous difference in the final look.

A seam ripper is not a sign of failure — it’s a sign of a careful sewer. Keep it nearby.

Understanding Your Pattern

For this tutorial, you can use any bloomer shorts pattern you have on hand, whether it’s a commercial pattern, a PDF pattern you’ve purchased and printed, or one you’ve drafted yourself. The techniques described in this tutorial apply broadly to most bloomer patterns.

Sizing

Garment sizing for children’s sewing can be confusing because it doesn’t always align with the sizing you see on ready-to-wear clothing tags. Pattern sizing is based on body measurements, not age. This is important: always measure the child you’re sewing for rather than defaulting to their clothing size.

The key measurements you need are waist circumference, hip circumference, and the length from the waist to wherever you want the leg opening to fall (typically mid-thigh for classic bloomers).

Most bloomer patterns provide a size chart with the body measurements each size is designed to fit, often with a small amount of ease already included. Ease is the difference between the body measurement and the finished garment measurement — it’s what makes the garment comfortable to wear and move in.

Compare your measurements to the pattern’s size chart and choose accordingly. If you’re between sizes, sizing up is generally the safer choice, especially for waist measurements.

Printing and Assembling PDF Patterns

If you’re working with a PDF pattern, print it at 100% scale (no scaling, no “fit to page”). Most PDF patterns include a test square on one of the first pages — a box that should measure exactly 1 inch or 1 centimeter. After printing, measure this box with a ruler to confirm your printer didn’t scale the file. If the box doesn’t measure correctly, adjust your printer settings and reprint.

Once printed, cut along the outer edges of each page and assemble them according to the pattern instructions, matching the alignment marks. Tape the pages together securely before cutting out your pattern pieces.

Cutting Pattern Pieces

Press your pattern pieces lightly with a warm iron to remove any folds or creases from printing and storage. Then lay them out on your prepared, pressed fabric according to the grain line arrows on each pattern piece. The grain line should run parallel to the selvage of your fabric — this is what keeps your garment from twisting and pulling in the wrong directions.

Use pattern weights or pins to secure your pieces, then cut carefully with sharp fabric scissors or a rotary cutter and cutting mat. Sharp tools are genuinely important here — dull scissors drag on fabric and create ragged edges.

Marking Your Fabric

Once your pieces are cut, take a few minutes to transfer any markings from the pattern to the fabric. This typically includes notches (small marks along the seam allowance that help you match pieces correctly), the top of the garment versus the bottom if the pattern is directional, and any fold lines for casings.

Use a fabric marker, chalk, or tailor’s tacks for this. Avoid marking directly on the right side of the fabric where marks might be visible in the finished garment.

Preparing Your Sewing Machine

Set your machine up with a fresh needle — a size 80/12 universal needle is appropriate for most of the fabrics recommended here. A dull needle causes skipped stitches, pulled threads, and frustration. If you can’t remember the last time you changed your needle, change it now.

Adjust your stitch length to 2.5mm for general construction seams. For gathering stitches, you’ll increase to about 4–5mm. For finishing seam allowances with a zigzag stitch, 2–3mm works well.

Set your seam allowance based on what your pattern specifies — most patterns use either ⅜ inch or ½ inch. Check your pattern instructions and use the appropriate guide on your machine’s throat plate.

A Word on Seam Finishing

Bloomer shorts are typically worn frequently and washed regularly. Taking time to finish your seam allowances — either with a zigzag stitch, a serger, or pinking shears — prevents them from fraying over time and helps your garment hold up wash after wash. It only adds a few minutes to the construction process and makes a real difference in longevity.

What’s Coming in Part 2

Once you’ve completed everything in this post — fabric selected and pre-washed, notions gathered, pattern printed and cut, fabric pieces cut and marked, and sewing machine ready — you are genuinely prepared to sew.

Part 2 of this tutorial series will walk you through the actual construction of the bloomer shorts step by step: sewing the inseam, the crotch seam, creating and attaching the leg casings, threading the elastic, building the waistband, and pressing and finishing the shorts. After that, we’ll move into the construction of the coordinating top and discuss how to finish the set as a cohesive, beautiful piece.

This preparatory work might feel like a lot before you’ve even threaded your machine, but experienced sewers will tell you that most sewing problems trace back to rushed preparation. The time you spend here pays off in a project that goes smoothly, fits beautifully, and ends up being something you’re genuinely proud of.

So do the prep work. Wash the fabric. Press it flat. Choose your elastic carefully. Print the pattern at the right scale. Cut on grain.

Then meet me in Part 2, where the real fun begins.

Have questions before you get started? Drop them in the comments below — I’d love to help you troubleshoot before you dive in. And if you’re sewing along, tag me in your fabric pulls and flat lays. Seeing what fabrics you’re all choosing is honestly one of my favorite parts of sharing tutorials like this one.