The fewer the better when you are starting out. Most of today's bows are fast enough that there isn't much difference from 20-30 yds, which is as far as I'd recommend any new bowhunter shoot regardless of ability. In that case you can try 1 pin and adjust to see how you like it, if that doesn't suit you, add a 30. Try to practice out to 40 though, to make the close ones a chip shot. 20-30-40 is a good setup, but I'd forget the 40 at live targets.