Do you guys 'clean up' for your escorts before visiting/them coming to you?
To what extent?
You will be amazed how much being freshly showered and shaved, and nicely dressed matters in this hobby.
Yes, hygiene and good grooming lead to better service by and large. Arrive freshly showered if possible. If not and it's an incall, she may be happy to let you take a quick 5 minute shower to freshen up. For grooming, you can either shave the downstairs or at least trim it up so the poor girl does not need to hack through the jungle using a machete to get to you. Brush your teeth and use mouthwash before a visit. If it's an incall, she may have mouthwash available for you. Be nice to her and it makes it easier for her to be nice to you. Basic golden rule stuff. Good luck!
...Shower, wash all the parts and don't forget your ass. Clean clothes, some guys wear shorts with casual shirts (think polo style) and shoes or sandals. Some business casual while others wear jeans along with casual attire. The point is be clean. Shave if you don't have a beard or moustache.
I do shower upon arriving at the in call location. Even if I showered before leaving home. It lets the lady know I'm clean and puts her at ease. I ask them to shower with me and most say yes. That way we're both confident about being clean and showers with beautiful naked ladies are fun. I had one lady wear a shower cap to protect her hair. I didn't mind a bit.
If you're coming from work to see her just shower when you get there. Most will have mouth wash you can use so use it.
Even if you've just taken a shower before leaving home, if the provider (typical of Asians) suggest a shower when you get there -- take it
To what extent?
I mean more along the lines of 'manscaping'
Showering is a no brain
So, yes, by all means, trim down there. If you aren't freaked out by it, shave the area too. It's not quite as scary as it sounds. Lots of gals in fact offer it as a service and will show you the ins and outs of how to do it yourself.
One gal recommended waxing in fact, which, if you're into a bit of masochism, really can be fun. She also recommend you keep a landing striip so that the stubble won't irritate her clit while doing cowgirl
If you've never shaved down there, then deciding to do it for the first time on the day of your P4P date might not work out.
I speak from having had many guys over the years who've nicked or cut themselves just prior to getting together; which then limits or even completely rules out, certain activities.
Just trim it up with some scissors. I do like it when the "boys" are clean-shaven but it might take a few tries before you get the knack of handling this without causing damage. 
I use one, it's made by Norelco, got it at WalMart. And I always use it a day before the appointment
Use a Philips body groomer...Works really well and easy to use.
Electric beard and mustache trimmer works for chest and pubic hair. You can set the depth. Manscaper for back and legs. Shaving it can leave a rough stubble. If you let it remain 1/4 inch long or so, it doesn't look like the jungle and yet is fairly smooth feeling. That said, I do shave my balls though everyday in the shower with a Mach3 blade.
This is elementary, and a matter of common courtesy...you expect her to be clean and fresh, right? Goes both ways...