What's the best way to make a good impression with provider?

Make sure you've read her website (assuming she has one) and know as much about her as she wants you to know. Don't just know it, respect it and adhere to it.  

doubly if you have a SO.  But just don't.  It will compromise your full identity, leave you open to theft or robbery.    
Use a hotel room or better go to her INcall.

If u do outcall spend the money and get hotel room the first time
it gives  the girl the security that hotel has your real name  so they can check u out.
in this day of fake pictures you do not know who is really coming last thing u want is a scene at your home.

This is what makes some gals want to gag when they see a guy who isn't spiffed up enough.

Shower, scrub, shampoo, shave, brush, gargle, and wear the cleanest of nice clothing like you'd wear out to a nice restaurant.  

Avoid eating foods with garlic for at least a week prior.  That's how long garlic lasts in the blood stream.  Pop in a couple of Tic-tacs about ten minutes prior to knocking on her door.

Make sure your shoes are made out of something that had parents.  (Gal's obsess about their shoes, so why would you expect them to not be concerned with yours?)

All this combined with following their rules to a Tee, and being unerringly polite will earn you their trust and favored position and I have found these to be unmatched assets where it comes to hobby satisfaction.

Bringing along a little gift (Check their website for suggestions.) also doesn't hurt.

...I included below. Then read everything else you find there.

....many gentlemen must disclose their identity, even if visiting a lady at her incall, or his hotel.  I would never knock on the hotel door of a gentleman whom I have not thoroughly screened; full name, place of employment, etc.  

It is also HIGHLY, HIGHLY recommended that women do NOT work at of your actual residence for many of the same reasons.

Being robbed in your hotel room, or incall for a lady, is one thing. Being robbed in your own home that you have to return to day after day is an entirely different matter. Only the most experienced and SINGLE mongers should ever consider inviting a provider into their home. That said, I do it all the time, but I am neither a newb, nor married, and if I were ever set up for a home invasion, I would be calling the police, not for assistance, but to pick up the body of anyone with the bad judgment to attempt robbing me in my own home. lol

I do it too, but I'm single and I only invite quality ladies into my home ... and I have a very protective dog. I have a sign in my garage that says, "If you are found here at night - You will be found here in the morning" Nuff said.

For most hobbiests, seeing providers in their home is extreemly risky & the OP seemed headed in that direction.  
I would not recommend a provider see hobbiests in HER HOME either.  

Being single AND experienced is the key.

It also helps if you don't present yourself as a "soft target" some women will do this and set up the john to be robbed at a later date. Guns, dogs, alarms, all say to a potential robber "find an easier target" lol