How to Sew a Swimsuit

How to Sew a Swimsuit
Sewing a woman's swimsuit is a simple process that can be performed by a novice in one day with a little attention to detail. Having a variety of basic two-piece swimsuits on hand can be useful if you plan to swim in natural bodies of water with dirt or silt that may damage or stain expensive store-bought suits. An additional benefit to sewing is the ability to customize the suit to perfectly match any occasion or personal tastes.


Difficulty: Moderately Easy

Things You’ll Need:
  • Swimsuit fabric Paper Pencil Scissors Sewing machine Thread Leather cord Panties
  • Swimsuit fabric
  • Paper
  • Pencil
  • Scissors
  • Sewing machine
  • Thread
  • Leather cord
  • Panties
Step 1
Choose two-way stretch swimsuit fabric. This is very important because using the wrong type of fabric will result in a swimsuit that does not hang correctly on the body. Test the fabric by holding a piece of it in your hands and stretching it from left to right, then stretch the fabric from top to bottom. The fabric should stretch easily and then resume its shape both times.
Step 2
Draw a triangle onto a piece of paper to create a pattern. The bottom of the triangle needs to be 10 inches long, the sides 9 inches for an A cup or small B cup bikini top. For a large B cup or C cup, increase the bottom measurement to 11 inches and each side to 10 inches. If you have a bust larger than a C cup, this swimsuit probably will not provide enough support for you. Cut out the triangle with scissors.
Step 3
Cut the leather cord into two 24-inch pieces, one 48-inch piece and two 40-inch pieces. Leather cord is available in assorted colors at craft stores and may be called leather thong or leather lace.
Step 4
Trace the triangle onto the wrong side of the fabric twice. Cut out the two triangles. Keep the wrong side of the fabric facing up and fold the top inch of one triangle toward you. Place one end of a 24-inch piece of cord in the middle of the fold with the end of the cord touching the tip of the triangle. Pin the cord and folded edge in place. Sew a straight line across the now flat top of the triangle approximately 1/4 inch from the edge, making sure that you sew through the leather cord as well. Repeat this process with the other triangle using the second 24-inch piece of leather cord.
Step 5
Fold the sides of each triangle in 1/2 inch. The sides should overlap the area containing the leather cord. Pin the sides in place and then sew a seam 1/4 inch away from the edge of the fabric on these folds.
Step 6
Fold the bottom of the triangle up one inch and pin into place. When you are folding the bottom up, the corners of the triangle will naturally overlap the sides of the triangle. Line the corners up so that they are even with the sides before you pin everything into place. This may cause a little bit of bunching, but that is normal. Sew the bottom fold using a 1/2-inch to 3/4-inch seam allowance. The larger seam allowance creates a casing in the bottom of each triangle. Insert the 48-inch piece of leather cord through the bottoms of both triangles to finish the top. You can now adjust the top to increase or decrease swimsuit coverage because the triangles will move freely on the leather cord.
Step 7
Find a pair of old panties that fit well or an existing bathing suit bottom to use as a pattern. When using panties, carefully cut open the vertical seam at the top of each leg to preserve the shape of the pattern. Open the panties or bathing suit bottom so that it resembles an hourglass shape and lay it onto the wrong side of the fabric. Carefully trace 1 inch around the entire panties to create a pattern with a 1-inch seam allowance. Cut out the piece along the line you have drawn.
Step 8
Fold the top and bottom of the hourglass in 1/2 inch with the wrong side of the fabric up. Sew the folds down approximately 1/4 inch from the edge of the fold.
Step 9
Place one piece of 40-inch cord across the top edge of the hourglass, with the wrong side up, so that even lengths of cord extend from both sides of the fabric. Fold the edge of the fabric down 1/2 inch so that it covers the cord, and pin everything into place. Use the second 40-inch cord in the same manner on the bottom of the hourglass. Sew each fold just less than 1/2 inch from the edge and be careful not to sew over the leather cord.
Step 10
Tie a knot in the leather cord where it emerges from the swimsuit casing. This will help keep the ties in place and prevent you from losing them when you're not wearing the swimsuit.
Step 11
Fold the unfinished sides of the bathing suit bottom in 1/2 inch with the wrong side facing up. You may need to make small cuts in the fabric where it curves in order to fold the fabric without its bunching. Sew along these folds. Fold the edges in an additional 1/2 inch and sew again to hide the unfinished edges of the bathing suit.

Tips & Warnings

When choosing fabric, wrap one layer of fabric around your hand and hold it up to the light. If you can see your hand clearly through the fabric, the material probably will become see-through when wet.

Article Written By Kittie McCoy

Kittie McCoy has been a freelance writer since 2008. She is also a part-time personal trainer and licensed entertainer in Las Vegas. She enjoys sharing her love of physical fitness and experience in the entertainment industry via her writing.

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