Start by spreading the fabric out, cutting the flat sheet cleanly in half lengthwise. If you’re using a plain sheet and want to add a personal touch, consider stenciling for added appeal.
All of my measurements will vary from yours, because mine are made straight to the size of the bedroom window, but this concept can be carried out in almost any size.
Top to bottom, I only needed a 50″ length for each window, and the bolt of blackout fabric measured 54″ wide, so I was essentially able to buy two yards of fabric (totalled $7.50!) and cut it width-wise to fit both windows. Had I not realized this at the store, I would have brought home fabric to length (almost 4 yards) and had a lot leftover.