you don't really have to get very creative to make girls happy, just "acceptable". girls that like going down on guys don't do it because it tastes good, and girls that aren't fans of going down on guys don't like it because it tastes bad (although this might be why a girl doesn't like going down on one person in particular).
with that said, here are just a few simple tips that could help:
- don't eat asparagus... it makes the swimmies taste funny and your pee smell weird.
clean thouroughly with soap, but be sure to wash away all the soap. no girl wants to think they're going down on a dove bar.
spray cologne or body spray near, but not on, your manhood... i can't imagine that stuff tastes good, but it'll help cover any musty smells that might linger down there.