You ask some expert "How do I do X with Y?". He'll tell you. He'll likely wonder what the hell you're up to in doing such a strange thing with Y, but he'll answer.
Also in the event you get an unusually helpful expert, he might point this out. Consider this your lucky day and feel free to ask follow up questions. Don't be discouraged by the pointing out being phrased along the lines of "What kind of idiot would want to do X with Y?"
r/Fitness does a weekly "Moronic Monday", a judgment-free thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. I thought this seemed like a useful thing to have here - after all, the concepts discussed on LessWrong are probably at least a little harder to grasp than those of weightlifting. Plus, I have a few stupid questions of my own, so it doesn't seem unreasonable that other people might as well.