I found it interesting that my cavies were terrified of scissors, but didn't mind the noise and buzz of the clippers.
Clippers, whether large or small, come with plastic guards that clip on over the basic blades. They permit cutting the hair different lengths. You would probably want to use the guard that allows the shortest cut without shaving him, Start around his genitals and move in an outward direction away from them. That way if you "slip", you are moving toward his legs and bum and it poses no problem. If you cut too much.......it's only hair and will grow back.
I make it a point to check my boys genital area weekly, usually at the time I weigh them, clean ears, and sometimes give them a manicure. Not kidding with the manicure reference. I don't cut the nails, having cut the quick too many times. I use a Dremel to smooth them and then apply some clear nail polish. This helps to make their nails less sharp and minimize tearing of the fragile skin on my arms and chest. Sounds like a bit of an overkill, but it works for me.
If you have a boy that is particularly well-endowed, you may need to clean his testicles and anal sac to avoid odor. That area seems to catch everything including smegma, lint, and even hay. I put the boys in my lap and sit them up with the back to my abdomen, and use a q-tip and a little oil such as coconut to clean them. One of the reasons that I recently had both boys neutered was because I couldn't keep them clean. Sparky had such huge testicles that he could barely walk and constantly emitted an odor. What a difference a week makes! His scrotum is beginning to atrophy, he is obviously more comfortable, and the odor (from both) has virtually disappeared.
Sorry that the images aren't too clear but he wouldn't hold still. His fur is slightly stiff around his anus and there looks to be urine on it. Is this because he has long hair and is white?
