I used to bite my nails. I bit them for about 21 years, and last year, almost to the day, I made the decision to stop. I had been working as a lawyer for a year and I started to notice people's hands more at work and at networking events (all that hand shaking I think). To me, it was very obvious when someone had short bitten nails. I started to think - if I'm noticing it on other people, people must notice it on me. I thought it looked unprofessional and a bit juvenile. So I made the decision to try to stop.
(By the way, I'm sorry but I don't have any "before" photos because I didn't have the foresight a year ago to think I was going to do a post on this.. Below are some of my favorite manicures I've had over the last year.) Anyway, here's some of my tips on how I quit my worst bad habit.
1. I started out by getting a set of acrylic nails put on. These can usually stay on for at least 2 weeks, which would give my nails underneath time to grow out. Plus, the acrylic is really hard - so hard that I could still put my nails in my mouth, but I couldn't physically bite my fingernails because they were so hard. I left the acrylics on for about 3 weeks to let the nails under grow. As an aside, I know acrylics basically ruin your nails, but I was starting from scratch and knew my particular purpose. I purely did it to grow some initial length.

2. After I got the acrylics taken off, I got a professional manicure done to even out the ragged edges. But my real step 2 was that I started getting gel/Shellac manicures for about 2-3 months. This also "ruins" your nails and makes them paper thin, but the trick for me was not physically being able to bite my nails. The gel polish is pretty thick, but still thinner than acrylics. Therefore, I was still able to do the action of putting my nails in my mouth without physically biting the nail off. It wasn't until about December of 2013 that I weaned myself off biting altogether and was able to move on to regular manicures.
3. After my nails had grown long enough to my liking, I started getting manicures every 2 weeks. I found that whenever the polish chipped, I was more likely to revert back to biting my nails, so my #1 tip is to always have a polished manicure with no chips. The prettier my nails looked, the less I wanted to ruin them.
4. As I finally completely stopped biting, I let my nails grow longer and longer - this was a mistake. Whenever I let them get too long inevitably at least one nail would break or crack, and I'm back to square one on that nail. I now keep my nails pretty short (like all of the above photos) to make sure I don't break a nail.
(This is not the above color - but it's similar and it's one of my favorites -
Essie "Chinchilly" is probably the color I choose most at my manicure place)
5. After 21 years biting my nails, they were very, very short. I had damaged my nails pretty badly but hoped that as the nails grew they would reattach to the skin. Unfortunately, after a year, there has been little to no reattachment. This results in me always wearing opaque nail polish because I just hate the way the nails look without it. I accidentally chose a see-through pale pink polish at my last manicure appointment, so you can see what my nails actually look like below. They aren't terrible, but I'm still self conscious about how they look "bare," or without opaque polish.

Finally, I want to say that I definitely did not quit cold turkey. I bit my nails a few times over the last year. But I usually caught myself doing it, stopped, and immediately filed the nail a bit to get rid of the rough/jagged edge. Despite a few biting setbacks, I think the thing that kept me going was looking down and seeing pretty nails. I now love changing my polish and I've found that it's a great accessory to an outfit. Plus it's fun to buy pretty polishes :)
So, yeah, this was kind of a weird/personal post for me. I don't usually talk about my life much on the blog, as you can tell. I'd love to hear from anyone who also used to bite their nails, anyone who currently does and is looking to stop, - or anyone who's got some favorite polishes to share! My collection is growing and growing, with Butter London polishes at the top of my list. I LOVE their glitters!