Oh wow...that was some awesome OP. Alright, advice time from the recident deviant.
1: Shaving your balls is easy. Simply get a good three/four blade razor, stand under the shower.
2: Stretch your skin so it's smooth.
3: Apply razor.
4: Shave.
5: Repeat in two-4 days.
6: In the long term: Grow a lot less sensitive to it all.
I don't tend to use any foam or gel... mind you, after shaving the skin is extremely sensitive and foam or gel can make it sting. Keep your razor nice and clean.
As for the itchiness, that's just being a man. When I'm among friends I scratch en-public. Mind you, when you scratch inside the pants, or adjust them only use your left hand.
And as for butt-hair, leave it. It generally itches a lot less.
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