Good luck.
As it has been said, being told that the client is a virgin is one of the least concerning things any SP has heard. If anything, it's probably a huge relief for her, since so many worse comments can follow "hi sex worker, I have something to tell you..."
Read some of the other virgin threads and get acquainted with the process of researching, booking, and following through with the appointment. Do you have any issues that could affect your performance, like porn addiction, poor social skills, etc.? Not trying to worry you, but it might be worthwhile to address anything like that ahead of time so that you can get the most out of your experience. At 30, there's no guarantee that you're going to get a raging boner at the mere sight of a naked woman like you assumed you would, especially if you haven't interacted with women regularly for a while.
Maybe this is an unwanted point or doesn't belong in this thread, but I'm not totally convinced that admitting to an SP that you're a virgin is beneficial 100% of the time. Is it possible that the physical and psychological demands of having to pretend that you know more than you actually do could improve your performance (and therefore enjoyment) of the appointment? I'd love to hear differing viewpoints on that. I feel as though we've never heard testimonies from guys who have attempted this.