How to Sew Spandex Into a Custom Bikini Top

Measure and cut out two triangular shapes from your spandex fabric. While you can make a bikini top with any type of fabric, swimsuit fabric (Spandex-based) is widely available during the spring and summer from any fabric store. The bottom of the triangle should be slightly convex.

Sew a hem along all sides of the triangle.

Sew a second hem if desired along the top sides of the triangle, but only if you have enough fabric and want to make your bikini top higher quality. If you want to add a liner, no second hem is required. Instead, sew in the liner, flip the right side out and stitch a line across both layers to keep the liner in place.

Fold the bottom of the bikini up to form a small loop in the fabric. This is the opening for the bikini ties. Sew down the fold, making sure to leave enough room for a cord to slide.

Add a segment of ready-made cord to the top of each triangle, long enough to tie behind the neck. Pass a segment of cord through the bottom of each triangle, long enough to tie behind the back. Simply tie off the ends of the cord with a knot. No sewing is necessary.