I don't think there are any rules that apply to all. Personally, I see no reason to waste time, start having sex as soon as you are both ready. You only go round once, better that you enjoy your time.

__________________
Lots of people talk and few of them know, soul of a woman was created below

I can't get through to her 'cause it doesn't permit
But I'm gonna give her everything I've got to give.

I hear your sweet voice calling
out my name
As I stare from a six foot cell
And from beyond I heard the words
Deceptively Yours