My first time was filled with anxiety and anticipation rolled into one. The thought of playtime on order whenever I want and no strings attached was great but I was nervous as well and did not know the etiquette.
As such, my first experience was more like the first date I ever went on in my life. Awkward with childlike inexperience. I spent tons of time on small talk and trying to get comfortable rather than just getting down to playtime (which I wanted).
Few things that I figured out along the way:
1) be clean and smell fresh (showered, brush your teeth, freshen your breath and a light spray of cologne is good) remember SP's are still women and they will react like women (most women don't like stinky, dirty men).
2) have the donation ready at the start either in an envelope or casually sitting on the coffee table (if she is visiting you. This avoids tense moments of how do I deal with this)
3) 5-10 minutes of chit chat to get a little more at ease (for 1 hour calls) then off to playtime (don't blow your whole hour trying to get to know her).
4) if you have refreshments for her, have it in sealed containers that she can open herself (she might be afraid of being drugged and offering pre-opened stuff could put her on edge)
5) before getting carried away, ask her about any restrictions so that you don't any backlash in the heat of the moment because you have crossed her boundaries.
6) treat her like a lady. She is an SP but you will get farther if you are polite, well-mannered and consider her physical pleasure too (DATY, mutual full body teasing, altering your performance or technique to suit her and you, body massage afterwards have worked well for me to get more mileage out of the YMMV formula)
7) have clean washroom facilities available (she might want to get cleaned up afterwards and most that I run into prefer clean facilities).
8) for your protection, keep the amount of money on you and ID on you to a minimum, nothing worse than trying to figure out what was in your wallet if it got stolen or left behind (not that it happens all the time but occassionally a crooked SP might try and pull something funny. I almost got jacked one time but my spider senses said something was wrong and I left before it got out of control and only lost $95 on that one).
Lastly, for a first timer it is hard to say who would be good.
Ladies who have been reviewed well like Ingrid or my personal favorite Morrigan Latour (used to be known as Pandora with Classy Ladies, she is coming to town this weekend!!) would be good starts.
Ultimately it is always YMMV (your mileage may vary) and personal taste that can make or break your first encounter. In theory you could set a date with any top SP and just because of bad chemistry it becomes a so-so encounter. Conversely, the SP might be a fabulous performer but her looks and body just don't do anything for you (some like big chicks others like spinners).
I would say you just have to TOFTT (take one for the team) and figure out what type of SP's you like. Part of the fun of becoming an experienced hobbyist is trying out all the different gals and learning what you like.
Beware though, this can be an addictive pasttime and a costly one if you let it get out of control.
Anyway good luck with your hobbying.