I found the best way was to trim with either an elctric trimmer or scissors until extremely short then with a new razor in a hot bath or shower and with lots of lather finish the job off. Its Easier if you have a raging hard-on. and afterwards lots of moisturiser or baby oil rubbed in to the scrotum and shaft.
Trim it down with scissors or clippers with a guard. A hot shower to soften the hairs, shaving cream & a good quality NEW rasor. Shave with the hair to avoid ingrown hairs while pulling the skin slightly taunt. Enjoy the results! Shave every few days to daily, it's is up to you. After a while it will become a very simple task. Bonus is you and your partner spending time in the shower grooming each other!
If I let it grow, I trim down as short as possible with a trimmer then use a depilatory cream. Results as smooth as a baby's butt and no worries for about 2 weeks.