You want to have your e-mail simple. You want to say something like I had a great time tonight or today depending on when for are going out.
Then you want to make sure you include your number so he can call, but if he does not call and choices to e-mail that is ok to. Some times people are more comfortable online.
The reason for this is because they can think about what they want to say they do not have to worry about answering questions fast. People get nervous to say the wrong thing so they prefer to e-mail.
I would not wait long to send an e-mail, I would send it shortly after you get home.
The longer you wait the more the person is worried that the person is not interested.
Not all men are pursuers some guys are very shy and tend to over analyze relationships, so they take their time in asking the person out again. Some guys get so scared of rejection that they don't even ask someone out. You will have to get to know his personality a little better before you can figure out if you should be the one to ask him out or wait for him to ask you.
Not all men are turned off by a women taking the lead because some times a man wants a strong women the times are changing and women are now going after what they want, they no longer want to wait. A guy is the same when it comes to asking a women out they are nervous and afraid of rejection. There is no difference there.
Some men do not even know where to begin to ask a women out. They let their fear take over and some don't even ask because they do not want to hear the word no. But you have to take these risk in love in order to find the one you are suppose to be with. It is ok to take the lead because you do not want to change who you are.
You want to follow your feelings so that you can enter this relationship honest.
You do not want to hold back your feelings to wait for him to take the lead.
You want to take do what you feel is right.
You want to show him your true personality.
A guy is thinking the same thing when he goes home after a date wondering if the person wants to see him again, if he said the right things, if the person likes him. They often go home thinking they blew it, this is why it is good when a women is open about her feelings.
Telling the guy she had a great time.
If you go home and send an e-mail he will not wonder how you feel about him he will know you are interested. It take the guess work out of the relationship. It creates a good start.
If you have anymore questions you can address any questions by putting Dear XXXXX on the question this way will get it and I can continue to help you.
I would love to help you further after you go on the date because you might have more questions. Thank you again for your question.