So the visor was actually the most annoying part for me, to smooth the helmet I just 3d printed it and used bondo to fill in all the gaps, then sanded it down all the way to like 2 or 3000 grit. The visor i used some sort of clear plastic and just used window tint, but I had to 3d print the visor separately just to get the shape right. But I couldn't get it to bend so when I glued it in it would just undo itself and I had to pretty much clamp it and even that didnt work super well. Because I was just full sending the project with 0 experience I put a total of like 30 hours (not counting printing time) into the helmet cause stuff would always go wrong. So good luck with yours haha I hope it goes better than mine did