I sometimes like to keep the down below bits trimmed. I have used hair clippers before (with the grade 2 attachment), I've also used modern multi-blade raors (a bit more risky but good for brush cutting, just don't go too far unless you want an itchy regrowth). The small type battery clippers that the barber uses around the neckline are also quite good, but I used to use my wife's and we are separated now so I didn't buy another pair. I don't think it is rude or disgusting to talk about maintaining one's hair if the question is asked. Just don't use an electric shaver.
When I was due to have my vasectomy, I was asked to clear the runway down under. I used my Phillips shaver. Due to the inconsistent and much more sensitive surface down there, much more of the folicle protrudes and is therefore going to end up inside the shaver. It was very painful!