Need help!! what should I do!?

OK so I think I'm ready for intercourse, I'm comfortable and feel ready, there's just one problem..I don't physically know how! I mean I'm so confused, It's not the kind of thing Du can just look up on Wiki-how and I don't want to get into bett with someone and be like.."er yeah sorry I would put out but I don't know how to." Will I just know when it happens..like will it come naturally? do I just Du know..open my legs and let him do the rest? wow, this is embarrasing, I won't ask any of Du guys to explain, but where can I find information!?