Seamless Reversible Bikini Bottom in 6 Easy Steps

Even if you’ve never sewn a bikini, this tutorial will teach you in only six steps how to make a side tie bikini bottom. It is a seamless reversible piece… like having two bottoms in one! I used me new Tatiana Reversible Bikini PDF Sewing Pattern, available in my pattern shop. It also includes a reversible halter top.

NOTE: Seam allowances are 1/4” (6 mm), unless otherwise specified.  Since the suit is reversible, we will use two main fabrics rather than a main and a lining.

STEP 1:  In fabric #1 Pin BOTTOM FRONT (2) to BOTTOM BACK (3), RIGHT SIDES TOGETHER.  Stitch the crotch area with a very narrow zig-zag or serge. Repeat the process with fabric #1. On ONE of the bottoms leave A 1.5” (4 cm) opening.

STEP 2:  Fold BOTTOM TIES (5) in half lengthwise, RIGHT SIDES TOGETHER.  Stitch long edges with a very narrow zig-zag or serge.  Make sure to stretch the fabric while you sew.  Turn RIGHT SIDE OUT with a loop turner of safety pin.  Remember that you will cut the ties in fabric #1 only.

STEP 3:  With bikini bottom in fabric #2 RIGHT SIDE UP, pin in place BOTTOM TIES (5) on all four corners.  Sew, leaving a ¼ “(6 mm) seam allowance.  Make sure to backstitch a few times. 

STEP 4: Place bottoms (Fabric #1 and Fabric # 2), RIGHT SIDES TOGETHER. Sew with a small zig-zag or serge just outside seam allowances.

Using ELASTIC GUIDE (7), cut one piece of elastic for front waist.  Using ELASTIC GUIDE (8) cut one piece of elastic for back waist.  Using ELASTIC GUIDE (9) cut 2 pieces of elastic for legs. 

Pin elastics, matching dots. It is not necessary to stretch the elastic.

Sew, using a short, wide zig-zag or serge.

Turn right side out through the crotch opening.

STEP 5:  On the crotch area, close the opening, sewing very close to the edge. 

STEP 6: Make sure all 4 bottom ties measure the same. Trim if necessary. Cut the ends of the ties diagonally and insert the cord ends (optional).  Using a pin to pull the strap is helpful.  Tie a knot on each end and cut the remaining close to the knot.

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