One thing that sets MY regular go-to guy apart from the crowd, is that he starts his session by showering WITH me, scrubs me down and sets the mood with some scintillating moves, under the warm water.
Beyond that...as others have noted. Don't over-do the oil or lotion...and be sure to clean it off with washcloth and dry with a towel when you're done. Don't just send them to the shower again ! Do it for him.
If you're offering "erotic" be clear up front, where your lines are drawn. Too many times, I've signed on for an erotic session, that wasn't anymore "erotic" than a massage, I've gotten at a legitimate spa. That makes
the experience disappointing, and my tip disappear.