if the stickers are too hard to pull off by hand, just take like a flat head screwdriver or a knife and just try and push on a side of the sticker so it wrinkles a bit and then it should be easier to pull off. if you have goof-off, you'll be able to get the extra crap off with no issues. actually, idk how well goof-off reacts to helmet plastic. i know that with weaker plastics, goof-off kinda melts the plastic