A country rube is about to get married and he asks his Pa,
“Pa, how can I tell if I’m the first feller Norma Sue has ever been with on our wedding night?”
“Well that’s easy son. Just do what I did on my own wedding night. All ya need is some red paint, some blue paint, and a shovel.”
“What the heck do I need those things fer?”
“Well son, you take the red paint and you color one of yer testicles red, then you take the blue paint and ya color the other one blue.”
“Really! And then what Pa?”
“Well then if she says that that’s the strangest looking pair o’ balls she’s ever seen, ya hit her with the shovel!”