I do enjoy the anticipation of waiting for the day of my next date to arrive.  Just relax, take some deep breaths and enjoy the moment when it arrives.

LLAP,
Swim

Honestly, it worked for me back in the day.

You can face it head-on, overpower it, soothe it, or distract from it.

To face it try writing down exactly what it is that's causing your anxiety (what are you worried/afraid of). Follow each worry to its logical conclusion/outcome. Remember to eliminate this evidence when you're done.

To overpower it try power-poses for at least 10 minutes. This sets your mentality into a "superior" state.

To soothe it turn on some music, take a bath, breath deeply (in through nose, out through mouth), and, starting from toes and moving all the way up, tense and release each and every muscle.

To distract it try doing math you find beyond your abilities. Actually work on the problem. Make it your mission to solve it. Math isn't the only option, of course, but you want to avoid stress-inducing problems (like focusing on an upcoming meeting, presentation, etc.).

These are cookie-cutter techniques for stress management. For myself I've found that music is all I really need. I try to match it to the type of date I'm looking forward to having.

That's not to say that I don't get excited about my dates, just that there's no anxiety. Rather than dwelling on the fun you're soon to have, take some extra time to bathe and groom and then shift your focus to an unrelated activity that you typically do to pass the time (tv, reading, whatever). This should allow you to give her a few minutes to settle in, rather than greeting her with a raging boner; she'll get you back in the mood tout suite!

you have done your proverbial homework (setting up an appointment with only well reviewed ladies with many reviews written by experienced hobbyists, etc., etc. etc.) then there is nothing to be worried about as you sit and wait for the lady to arrive. Your chance of a being physically harmed or robbed is virtually zero. Your chance of being caught in an LE sting is virtually zero. Your chance of her not showing at all are virtually zero. Your chance of her showing up disinterested and disorganized is virtually zero. If she has pages of positive reviews for appearance, the chances that she doesn't look anything like her photos is very small. If she has pages of positive reviews for performance, the chances that you won't experience similar sexual satisfaction is virtually small. If you are worried about your performance abilities; don't be. She's not grading you on whether she is sexually satisfied. A non factor.  

So as you can see, the most likely outcome is that you will have a GREAT TIME. So relax. There is NOTHING to worry about at all beforehand.  In my experiences the worst thing that can go wrong (again assuming you've done your homework prior ) is that you don't click completely with a ladies personality. Okay, not a big deal. Try to enjoy your time to the best of your ability and when its over, just move on. In most cases it prob. won't be an awful experience, most likely just an average one. And that's fine. With hundreds of ladies to choose from, the next lady will most likely exceed your expectations!

We've all be there before.  Even now I still get a bit nervous when I'm meeting a lady for the first time.  Music seems to be a great help.  Let's me focus on something other than.

Works for me.

former athlete, I always had a skip in my step on game day.  Once the game began, I would settle in and play as if it were practice.  

On a day when I am meeting a provider, I have that same skip in my step and often look at my watch and say to myself, "only 4 more hours until . . . ."  Once the date begins, I relax and enjoy.

Same routine day or two before--get plenty of rest, stay hydrated, etc.