Don't!
But seriously, folks: The most important things are:
- Focusing on the virgin, not yourself (this also applies, if you're both virgins).
- Don't expect yourself to get anything out of it.
- Don't rush it.
- Don't push him/her into doing it if he/she regrets halfway through.
And now, assuming that the virgin is female:
Probably the best thing is to make sure that she has an orgasm even before your start sticking your Big Willie into her. There are multiple ways of achieving this - think of one yourself. Furthermore, as always, when you fuck, give her the control: Lead her hands down to be able to make space for the thang. And let her come on top of you.
But in general, the top advice should do: Keep calm - and don't forget to end it all with a nice "oh my god i'm coming" face!