I tried shaving once. Never again!!!
All I did was get a couple of slight nick and it was like Sweeney Todd had been doing overtime down there.
I use something called Nads (no really) and slaver it in for the ten minutes. I've even used it on my arse crack with good results.
One word of warning: do it at least a few hours( or ideally the day before) as it smells quite ripe.