Step 1: Inspect Gamepad
Fully functional, but the buttons are bright and slick. They don't feel very good in your hand. The directional pad on the left is slightly messed up. It's about as personalized to my grip as a No. 2 pencil.
Oh, no, this will never do...
Step 2: Increase Ergonomibilityness On The Top
Step 3: Retro Shoulder Pads
Repeat the process for the shoulder pads (L1 - L4), except of course with rectangles. Squish and mold the sugru to your liking - I didn't go too crazy molding it to my fingers, in case I didn't like the position later on, but also didn't leave it completely smooth. It looks odd, but feels nice.
Step 4: Smoothing
I liked this result better than leaving it all finger-printy. That would drive me nuts (although I'm a bit of a perfectionist with things like that...I like smooooooooooth...).