With wrong side facing out of tank bodice, pin right side of hem facing to wrong side of tank bodice. Make sure to match center front, center back, and side seams.
Side seams of bodice should be pressed back (raw edges finished), side seams of hem facing pressed forward with seam bulk trimmed down).
Stitch hem facing to bodice at 1/4'' seam allowance.
Press seam flat, then press seam up towards bodice.
Snip 1/8'' into center front and center back notches of hem facing to maintain notch after pressing.
With wrong side of bodice facing out, press bias hem raw edge inward 3/8'' as depicted below. Take your time making this edge nice and straight. Make sure you mark center front and center back of tank bodice as indicated in instructions.
A close up view of how it should look:
Optional Step: Understitch seam allowance of hem facing to bodice (wrong side facing out of bodice).
Results of understitching hem facing seam:
With right side of bodice out, flip hem facing up.
Pin as needed matching side seams and center front, center back notches).
Edge stitch hem facing to bodice, 1/8'' from edge of facing, practice starting on back bodice.
Take your time, remove pins and straighten out edge while smoothing out facing as you go.
Press your hem facing to remove any rippling.