Hi liskeardgirl. Collie pup, awww!
Pups will nip and mouth for attention, so you are right to look at stopping that early.
I tried to go back a while as I know there have been a few similar questions on AB recently, but I couldn't find the relevant.
When does your pup bite? During play? For attention?
This brief article is really accessible, and says everything I was planning to type anyway!
http://64.233.183.104/search?q=cache:dNzQwrmwu LEJ:www.azhumane.org/education/behavior/Behavi orInfo/puppynipping.pdf+dealing+with+biting+pu ppy&hl=en&ct=clnk&cd=1&gl=uk
Hope you find it useful, and that you solve your issue. Collies are brilliant (I have a soon to be 3 year old boy), and if you raise your pup well, you will have a lifetime of pleasure. Remember what Collies were bred to do: they WILL round up bikes, kids, moving cars, the postman etc. if not occupied and stimulated mentally and physically. Also, be wary of small children, as Collies can often nip heels. Young kids are odd, with their noise and sudden movement, so ensure that any children that visit or live with you are calm, quiet and relaxed around your pup. I am sure you know all this already, but it's best to be safe rather than sorry :)
Many warm wishes for a lifetime of happiness.