The best way to get them used to being handledis to handle him daily. Since he is young, I suggest taking him outevery day, if he doesn't like being on his back, spend a week or sojust putting him on his back for a minute or 2, then increase the time.after about a week, start playing with his feet, handle them, pull hislegs out while he is on his back. This kind of handling will ensure heis easy to clip nails and it makes vet check up so much easier!
My boys were never handled like that daily, I still can't put them ontheir backs but my does have been handled like that from day one andit's so nice to handle them and the vets love dealing with them!
As for cutting nails, that depends on the surfaces they are running on.A rabbit who has grass/cement to run on is going to need less nailtrims than a rabbit who is always on wire, tile, linolium. I findbabies don't need their nails cut so much, they are sharp but cuttingthem doesn't help. For rabbits who develop cronic sore hocks, it's bestto cut nails often (I cut my boys' nails every 2 weeks) to preventpressure being put on the hocks. Some rabbits need them cut once amonth or every 2/3 months.