I found that it helped to just keep painting them so they looked halfway nice, and once they got past a certain length i liked them so much i found i didn’t want to bite them any more! They look soo much nicer long. Having a nail file handy, as has previously been mentioned, is an absolute must too – those scratchies will be the end of it otherwise!
False nails can help grow the nails but it makes them very weak so long term isn’t perhaps the best solution. I’ve got this great stuff called Nu-Nale cream, basically lanolin, that makes them much stronger and keeps the water out. Almond oil (or similar) is pretty good too if you’re of a veggie/vegan persuasion.