I know this thread is a little aged, but seeing as I swim all the time on a swim team and cant wear suit with skirts on them due to drag, I have gotten pretty good at taping up and not making it hurt.... too bad. I hope I am not to descriptive for some of the audience.
All you need is shaving cream, razors, petroleum jelly, kt tape (your skin color), and duct tape (you skin color if you can find it).
Clearly the key is to be completely shaven, everything from your belly button down under and back up above your butt. Shouldnt have hair there anyway, hehe. So use your shaving cream and razors if you need it.
Use the jelly on the tip of your thing and a tad further up than you think (trust me) dont skip this.
Then take 2 long strips of duct tape and tape your lower regions in an x shape manner so that pressed up between your legs. Be sure to not go so wide that the tape will show when you have your suit on. It should be snug! After that, take 2 smaller strips and tape vertically the ends that are on your behind cheeks so so that those 2 strips that have a lot of tension stay put from a piece of tape with less tension. then take another strip and tape horizontally the tapes on your groin so they dont pop off and they stay put. then take 2 strips of kt tape and tape the the edges of you crotch between your legs so that it makes the duct tape less obvious if you do breast stroke, and it a lot more friendly on you legs as far as friction is concerned.
I swim in the pool this way, butterfly, back stroke, free, breast stroke, ect... and it holds for hours, even went biking for 4 hours and ran some and still held. Took me a lot of practice to get it right. And with swim team, have to wear suits that wont allow you to hide anything with a little skirt thing and cant wear shorts.