Essentially the lovely lady in your sexy duo rests on her side with one leg straight up in the air and the other flat along the bed. The hunky male counterpart of your coupling slides home between her spread legs.
Now here's where the fun alterations can get interesting, your bottom leg can either come out perpendicular to your body or can run straight with her spine, both allow for different feels so experiment! The man can straddle you either with one leg up or kneeling on both legs (if your leg is straight down.) Experiment to see what is comfortable for you and yours.
For an added bonus either of you can get to the lovely lady's clit, or breasts.
This is also a favorite position for pregnancy because it allows for deep penetration and no pressure on the abdomen.