Billie One Piece Written Directions

Printing & Assembling the Pattern

Choose either US Letter, A4, or A0 format, all of which are included inside your download links. Open up your desired file and read through the initial instruction pages for more information on how to print and assemble this pattern. Note that if you're using the A0 verison you will need to pull up either the US Letter or A4 formats in order to access the direction pages.

This pattern is layered, so see the instruction pages for information on how to use the layer feature so that you can print out only the size you need.

Choose what coverage option you will make and review which pattern pieces you will need. Print and assemble your pattern according to the provided instructions, then you're ready to begin!

Video Tutorial

This pattern comes with a video tutorial, and we strongly encourage you to use this resource. Some of the techiques in this pattern are better shown versus illustrated, so you may have an easier time by using both the video and written directions. You can find the video at the following link:

Pattern Options & Modifications

There are many ways to customize this one piece! All the ways stem from the top front piece. In the video we demonstrated the twisting technique, and here are some other options:

1. Knotted* / Twisted top (shown in these directions and in the video)

*For making a knot you may wish to reduce the center width of the top front so that the knot isn't too thick

2. Using the top back piece as the front for a more skimpy look

3. Leaving the top front piece as-is for more coverage

4. Adding in an elastic scrunch

5. Adding in a drawstring


You should have 4 pattern pieces in total, 2 of those for the top section and 2 for the bottom.

In each pattern piece you will cut 2 in your fabric. For reversibles, cut 1 in each fabric for all your pieces.

If you're making your suit with a knot or twist, you may choose to make the lining and self fabric the same for the top front piece (Piece 1) for a more minimalistic look. For all other options you can use whichever lining you wish.

In the end you should have a total of 8 pieces, 2 in each pattern piece.

Step 1

Now we have all our pieces, and we’re first going to sew and attach our elastic.

Match each piece with its duplicate, right sides together. So match the top front with top front, top back with top back, and so on.

For the top pieces, sew and attach elastic to the armholes, the neckline, and the waistline/bottom line.

For the bottom pieces, sew and attach elastic to the legholes and the waistline.

Make sure you're leaving the "tab" areas completely untouched!

We strongly encourage you to use a basting stitch (long straight stitch) before sewing. This will tack down the fabric before you go to sew elastic, and it will make the elastic application go much smoother. Just remember the basting stitch needs to be removed or broken before the suit is finished, otherwise the suit will be too tight and you will likely hear the straight stitch breaking!

You will use a 3 or 4-thread overlock stitch for this, or a zig zag stitch if you aren't using a serger. If you have an elastic foot or if you're skilled with elastic, you can sew the seam and attach elastic at the same time. However, some prefer to split the process into 2 steps.

For more information on how to sew elastic, click here.

Step 2

All of our elastic is attached! Now we can move on to attaching pieces together. First we are just going to focus on the top pieces, as we are going to treat them differently than our bottom pieces.

So get your top pieces out and take your top FRONT to the right side. At this step you may decide to do a twist or knot. If you do this, just make sure you twist or knot fully so that your right sides end up being up still. If you need a better visual, please refer to 6:40 in the video tutorial.

Whether you decide to do a knot/twist or leave it as-is, your next step is inserting the top FRONT inside of the top BACK. Make sure right sides are going to be together before you begin this process. Line up the straps and the sides, and pin. Your top front should be fully encased inside. Sew down across all four layers to secure the straps and the sides, and this will attach your top pieces.

Again we are not touching the "tabs", so once this step is completed you should have everything sewn excluding the tabs.

To sew the straps and sides down, you can use a straight stitch or an overlock stitch. If you use a straight stitch be sure to mind the 1/4" seam allowance and then trim off the excess once you're finished sewing.

When sewing the sides, it is easiest to sew the inner two layers first with a basting stitch, and then using a regular straight stitch to sew down all four layers. This prevents the fabric from sliding too much and overall makes it much easier.

Step 3

Now we're going to focus just on the bottom pieces. These are going to be treated the same as how we did the top pieces, except when it comes to sewing down the sides.

Take the bottom front piece to the right side. (You could also do this with the bottom back piece, it doesn't really matter. For full coverage it's easier to take the bottom front to the right side, but for cheeky it may be easier to take the bottom back).

Insert the bottom front piece into the bottom back, with right sides together. First, align and pin the gussets together. For this seam you will sew acorss all four layers of fabric like how we did for the top pieces. You can use either an overlock stitch or a straight stitch, trimming any excess if using a straight stitch.

Step 4

The gusset is sewn, and now we need to attach the sides of the bottom front piece. We're going to do this in a different way so that we only sew through two layers of fabric. Your bottom front piece should still be inside of the back, and right sides together. Line up each of the sides. Your tabs should also be unsewn at this part.

Focus on one side seam at a time. There are four layers of fabric that make up the side seam. Separate theses four layers into two and two. When you do this your layers of two should have right sides together. You'll want to sew down side seam in one continuous seam, but only sewing two layers instead of 4.

If the photo is not helpful, visit 8:55 in the video tutorial for more visuals. This is tricky to illustrate and is better shown in a video than drawn!

Using an overlock stitch or zig zag stitch, sew each of the sides in the manner described. Your tabs should still be unsewn.

The reason we sew it this way is because we'll be able to pull the tabs out so we can fully access them to attach the top into the bottom!

Step 5

Now we're ready to attach the top into the bottom. First, take the top piece all the way to the right side. Since the tabs were left unsewn you will be able to do this through one of them.

Then you will insert the top piece into the bottom piece, right sides together. Before you do this, double check not only that right sides are together, but that your front panels and back panels are going to be attached correctly. Try not to make the mistake of attaching it in backwards! You can either clip into the seam allowance of your tabs to mark which sides are the front or back, or you can make sure the correct panels are both facing up. For instance, if your bottom back piece is facing up, make sure you insert your top with your top back piece facing up.

So insert your top into your bottom piece, and now line up the tabs. You may need to do this one side at a time, as it requires you to pull out the tabs from the bottom piece a bit in order to get them all lined up.

Once you have the tabs lined up, sew across all four layers to secure them together. Here you can use an overlock stitch, straight stitch, or both!

Step 6

The final step is taking everything to the right side. To do this, seam rip a 2-2.5" hole somewhere along an existing seam. Doing this close to the gusset is usually pretty discrete. Then, through this hole take the entire suit to the right side. The last step is finishing off that hole, and you can either use a straight stitch on your machine or an invisible stitch by hand. It is easiest to finish off this hole if you stretch it all the way before sewing, as this will curl in the edges of the fabric nicely.

That completes the Billie One Piece!