1st time can be nerve-racking, but I'm sure you'll have a great time!
Assuming you have no points on AW yet, you're an unknown random guy to her. I think she'll just be glad to find you're not a nutter!
If you're "clean & well-presented", & friendly, you'll get on fine.
I don't know how long your booking's for, but I've found asking to take a quick shower first lets them know for sure you're clean. Trim fingernails helps too.
Enjoy!