Originally Posted by QuiltE

I'd start with the rectangles and get it figured out first, then move to the HST.

Sandwich together two rectangles, both with right side up.
Draw diagonal from corner to corner.
Take the top one on the right and match with the bottom on the left, and sew .... one long blade made.
Repeat for seocnd.

Square and trim to the width/length you want ... then make your HSTs to match the width.

I always oversize when making, then trim nice and square.