I didn't find anything helpful on a quick google of 'positions virgin pain,' or whatever, but a lot of foreplay and being open and wet would generally take care of the problem. The most important thing is her being relaxed and ready. My suggestion would be missionary, as she can be completely relaxed and passive if she wants, which is appropriate for the moment.

Oh, the guy who was my first time was way more gentle and gradual than he needed to be, which was absolutely sweet! It was so cute. I think he went about a quarter inch in, slow, about twenty times before he went a half inch in, etc. If she's begging you to put it the rest of the way in, you're doing fine!

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