had tried few times,
1) make sure water is clean without soap and both of you had washed
up. (In the water you action don't be too fast "friction")
2) don't ever do half way in the water then half way above way, you
can do above water first then ends in the water.
3) no rub soap over "that place", not even soap on the body. high
chance to get infection.
don't catch a cold 
