I've found it's more how she drives it, ie her favourite position. Most of my partners have come riding me or me fucking them from behind. Then again, we all like to try something different from time to time 😉
There is no definable way really, you're lucky that you've made this connection. For every guy who trusts me with a pic (or pics) of his wife, I would say about 20 don't go through with it.