1. Hold your rabbit upside down in your lap
2. Push the hair on the foot down and find a nail. If you have white rabbit or "broken" colored rabbit, it will be easier to see the "quick" (the blood supply in the nail). Clip just the tip of the nail. If you clip the nails regularly, this is all that will be required. In my 3 years of raising rabbits, I have never cut the quick.
3. Sit your rabbit up and put him back in his cage.
There! You're all done!
A week or so before you go to clip your rabbit's nails, hold him in your lap upside down daily. If he struggles, do it for longer. This will not only teach your rabbit that nail clipping is easy peasy, but it will also give you confidence and that's the most important thing when clipping your bunny's nails. If you seem scared or overwhelmed, your rabbit will sense that and nothing good will come of this experience.
Rabbits have 4 nails on each back foot and 5 nails on each front foot. Make sure you clip the dewclaw on the inside of each front foot (the back feet don't have dewclaws). It can curve and be hard to clip if it gets too long.
I recommend clipping your rabbit's nails every 2-4 weeks.