Growing Out my Nails... or Keeping them Once They're Grown

I don't know why but it's kind of gross talking about growing out my nails, but oh well. I haven't bitten my nails since I was 13. When I started school, that changed and, much as I tried, they stayed short for a solid year. During summer they grew back, then when I started school again back down they went. When I started my break from school this winter, they didn't grow back. Fortunately, over my Spring Break vacation I must've had enough stress relief that my nails came back once again. Now that I have them back finally I want to keep them around! Lately, I've been using this 7-way (or 7-step or 7-side or whatever) nail buffer file to keep them that way. My nails grow square and then break where they connect to the nail bed - ouch, so whenever they grow too long, I make them rounder and shorter, then use all 7 sides of this starting from step 1. I'm pretty sure these files are originally intended to use on the surface of acrylic nails, but no matter. They are soooo smooth on the edge when they are done -- salon manicure smooth. And so far it's been fantastic for keeping them growing!