|Boobless as I am, I like having something between me and my shirt to keep things from showing through. So, whenever I make a pattern that would show bra straps, I add a shelf bra. Here's how I do it...
1) Using the front and back pieces of the original pattern (Kwik Sew 2741 was used here), I traced the neckline and side seams and center front down about 2 to 3.5 inches. This measurement depends upon the size of your bust. Mine is small, so I use about 2".
2) For the front piece, I measured from the top of my breast (where the top of the camisole would be) over the breast and down to where the bra band would run. I transferred this measurement from the top point of the camisole pattern straight down. This is where I marked the deepest part of the curve.
3) For the back piece, I matched the side seam from the front bra pattern and drew a line straight across.
4) On both the front and back pieces, I subtracted 1/4" at the bottom of the side seams tapering back up to the original line at the top. The pattern is ready.
Sewing the bra in:
1) Sew side seams for both camisole, and bra.
2) Baste the top edges together.
3) Measure elastic and make and match 1/4 marks.
4) Sew directly on around the bottom. I used my cover stitch machine, but a zigzag would work.
5) Finish top.
6) Try on and pin bra cups in. Zig zag these into the shelf bra.