I can help you out. I am a slave in a BDSM relationship, and Master makes me keep myself hair free from the neck down.
The first few times you shave, it's likely gonna leave razor burn, bumps, ingrown hairs no matter what you do. It's not too bad, but does itch like hell for a few days. If that happens, don't try shaving again until everything is healed up, or you will cut open the bumps and it will get worse.
If that hasn't scared you off, this is how you get the best results:
First buy the following:
a brand new razor, a good one with a few blades. I use a woman's razor because they are made for more sensitive skin and have little guard wires to help prevent cuts.
You will also need some baby oil and some shave gel; the best kinds are labeled for shaving the bikini line and advertise that they reduce bumps. You will also want some diaper rash creme.
Oh and be trimmed down there first, you can't shave long pubes...
Once you have all that, start by rubbing in the baby oil and let it sit for 10 minutes or so, it will soften the hairs and help lubricate the blade while shaving.
Then, get in a very hot shower, and let the water wash over your balls for a bit. that will open up your pores, further soften the hairs, and help prevent irritation.
Next, step outside the stream and apply a generous amount of gel and shave. Don't go against the grain, that causes ingrown hairs. Also rinse the blades often and re-apply gel as needed. Some bits down there can be awkward to shave - take it slow and use your free hand to hold things taught to give you a smooth, flat surface.
Then, rinse GENTLY, don't use any soap down there (it will dry out the skin), and carefully pat it dry (don't rub) with a soft, clean towel.
Finally, gently apply some diaper rash creme which will help keep it moisturized and reduce any swelling or itching. Don't wear any clothes that chafe for a few days.
It gets easier every time and now I never get bumps or rashes, so stick with it