A bit more progress. Had to stop because my fingers hurt.

Uh.. I prefer to wetsand, just because it's "cleaner." Although I'm not sure I wetsand in the proper way, so just sand however you want.

As I mentioned before, if you want to paint over layers, that's cool. You can see my original rust colored primer, and the pinkish-white areas that's Bondo that I added probably about four years ago?

You can also see some of the original sanding marks that paint has filled in, aswell as the original white of the helmet.

About sanding.. I'm using 180 grit because I've noticed any lower grit starts to tear up the fiberglass pretty bad. So 180 does this to a minor extent, but still works great. Eventually I'll go 220 so smooth out the scratches and stuff, though paint also does this! Paint covers up a lot of little mistakes. After that a quick once over with 400 grit, maybe. Not there yet so who knows!

You could probably also get away with using a small power-sander or something like that, but I'm doing this all by hand. A little more painful but I actually like sanding a lot! So I don't mind if this part drags on.

Anyway, if you have any questions, please ask!