For this video we used Kwik Sew pattern number 3239.
1) For these bikini bottoms we wanted to line the entire bottoms and would also like to have all the seam allowances enclosed so they will not be against the body when you wear them. Here’s how to do that: Layer your pieces in following order: back piece (right-side up), front piece (right-side down), front lining piece (right-side up), back lining piece (right-side down). Pin the layers all together at the side seam and crotch.
2) Set up your machine to a regular zigzag stitch. If your seam allowance (as listed on your pattern) is 1/4” set the width of your zigzag so it is 1/4” wide and stitch along the edge of your fabric. If your seam allowance is wider than 1/4” you will want to sew your seam using a long, narrow zigzag stitch following the seam allowance your pattern calls for. Then trim your seam allowance down to about 1/4” and stitch the cut edges together using a shorter, wider zigzag stitch. We show how to do this procedure on our one-piece swimsuit video: http://fabricana.com/blog-item/no-serger-swimsuit at about the 3:30 mark. Turn your swimsuit right-side out.
3) Next we will add the elastic to the waist and leg openings. Stitch your elastic into a loop using the seam allowance your pattern calls for and making sure your elastic is not twisted. To quarter your opening, select either your crotch seam or your sideseam as a starting point and place a pin. Find the halfway and then quarter points as shown in the video and place pins at these points. Next we will quarter the elastic, using the seam as the first point. Mark your halfway and quarter points and mark with pins. Match up the quarter points on your elastic with the quarter points on your opening and pin in place (make sure you use the longer elastic loop for your waist opening). We suggest matching the elastic seam allowance with the quarter point on the back of the leg and the waist openings. Use the same procedure to prepare your other two openings.
4) Stitch your elastic to your opening. You will need to stretch the elastic to fit the opening but make sure to not stretch the fabric. Once the elastic is stitched to the opening, fold over the hem using the edge of the elastic as a guide (and pin if you wish), topstitch in place from the right side of the bottoms using a 3-step or 3-part zigzag stitch. Stretch the elastic until it lays flat (you don’t need to stretch the fabric). Repeat this step on the other two openings.
Congratulations on completing your bikini bottoms!