1. Let her be on top or in control. She'll be more relaxed for her first time.
2. Use plenty of good lube.
3. Go slow and let her control how much & fast.
4. Use plenty of good lube.
5. Start with oral, move onto finger(s), toys, etc. first. If she can relax and enjoy the smaller steps first you'll be miles ahead.
6. Use plenty of good lube.
7. She will quite likely want some kind of buzzing toy busy up front.
8. Use plenty of good lube.
That is a pretty abbreviated but you get the idea. Ohh, did I mention lube?