Yep, you'll need to sew it onto the undersuit along with the 2" elastic straps. I used stick pins on the undersuit to layout the patchwork, then made a paper template based on the pins. After that, I cut the material, then had it sewed onto the suit. The toughest part was getting the elastic tight enough (but not too tight) so it looked okay. Just take your time and you'll be fine. You've done a great job so far and overcome a lot.