weekly manicures and keeping the cuticles soft helps.
Wear gloves or keep your hands busy when you are anxious.
Setting a goal for a special event helps too.

you should paint your nails and then dont bite then because thers nail polish o it and it tastes bad so just paint thenm every time you feeel like biting then

I agree with the suggestions below... except the one about garlic.. I don't understand how you'd do that.
But paint your nails, or if you're not too good at it get a friend to do it for you at least weekly and make sure it's a nice design that you don't want to spoil. Also, ask your friends to tell you off whenever they realise you're biting your nails!
The brighter the colour is the better, because then you're more likely to spot it before you bite! Also, if you're really good at nail art and have nail art pens, you could even write 'don't bite' on each nail or across one hand ;) hahah that last idea probably wouldn't help but it might look cool x

i had a very bad nail biting problem too and what i did was just always wore nail polish and whenever i would bite my nails it would taste discusting so i never did it again, it takes a while to stop tho.

some times they sell this clear nail stuff-it looks like a top layer to nail polish but it tastes terrible! you put in on your nails and the surrounding skin area make sure to get one that tastes gross one time i got one that tasted like mint haha i kept biting my nails right off

how?

Use garlic, it tastes so bad, and your nails are going to grew up.

I agree, I find that using nail polish prevents me from biting my nails

thks :)

Apply nail polish and when you go to bight them it will taste harsh and go all over your teeth, i'm sure you won't bight them after that.