Hi Ambera, as VC says do have a read through the main site if you haven't already!
It does get easier with practice and it's natural to feel nervous the first time (and for a long time afterwards- I still get nervous after many years). But you do develop confidence and get into a routine after you've done it a few times. It does get easier as you get used to it.
When someone knocks at the door I look through the spy hole (if there is one) to make sure he is on his own and as far as possible looks nice and normal. I open the door fully dressed (in sexy gear but no nudity) with a big smile. Welcome him in, say hello, offer a drink, take his coat (all within the first 2 mins or so). If he doesn't automatically offer the money, ask "do you have something for me?" or "Would you mind if we got the business side out of the way?" within 5 mins max of him coming through the door. Always, always count the money.
After that I just put a hand on their leg or start snogging them and it tends to go from there!
Good luck
H x