It works differently depending on the WG.
Do you just pick her up somewhere and she gets in? Does she know places to park up? This is the most likely.
will she blow you while you drive? That's both dangerous and illegal.
Be aware that if it takes place in your car, make sure she takes her knickers with her afterwards (if of course she was wearing any, my ex-gf never did ), plus any earrings etc which are liable to fall off and be found by your missus (if you have one).
Also be aware that the perfume the girl has on is liable to linger a long time. It's a small enclosed space and she'll be possibly rubbing it all over the surfaces during the act.
If you decide to go ahead, when you contact a WG simply ask her what her MO is and she'll tell you.
Don't forget smoking!
If she does and you don't, nor you family.
You may say no smoking in the car but her clothes may well bring the aroma with them.
She may want to smoke outside your car but if the windows are open, it will drift in.
Drugs, double dangers if she should want a different 'blow' to you!
The smell and aromas, again lingering.
Or worse, debris and/or fallout stays in your car, then a nice loveable Police or Customs dog takes an interest.
Pesonally I have done many Car Meets without any major problems and only one minor one.
Minor one, the girl arrived in her car at the chosen location, thought that I was too old and drove off.
Others have involved picking the girl up at a chosen location and heading off to somewhere I know.
Minor problem, ca parks were closed off;
https://www.ukpunting.com/index.php?topic=292011.0Met the lady at an agreed location, two cars parked side by side, one empty, one steamed up and rocking about, might attract attention.
Meet the lady at location suggested by her and you jump into her vehicle, easy for you to walk if you don't like the look of what you see;
Not my review;
https://www.ukpunting.com/index.php?topic=290051.0