i bought one of those sally hansen french manicure kits recently. You put on a base coat, then the little tape things, paint the tip part w/ the white polish, wait to dry and then take the tapes off and paint with the nude color (all the instructions come w/ it).
All of that may sound easy, but honestly IMO it's not. I went through all that and my nails looked like a 2 year old did them, it was so annoying I took it all off with remover after spending a VERY long time working on them, ugh! Kutos to anyone who can do a good french manicure at home, there's a real art to it