Hi fergalicious and welcome to SAAFE

If you do search for 'screening', 'spotting timewasters' and also maybe 'outcall safety' you should find a few threads with people's ways of doing this already, but the short answer is that the timewasters generally give themselves away fairly quickly and all it takes is a bit of practice to spot them; there isn't really anything you need to know from them bar the day and time they want to book and how long they want to book for, plus whether they want incall or outcall if you're offering both?

I don't take bookings by phone, only by text and I have very few problems with them messing me about; others prefer calls and some use email too. There are things they say which you'll learn to recognise (many are listed in the Spotting Timewasters' thread), and even ways of speaking which your instincts will learn to pick up on, but the best way to learn is to do it - your instincts will rarely be wrong.

As far as screening out punters who are genuine (in that they will actually book and turn up) but unpleasant or undesirable for whatever reason, my screening is basically 'do I want to see this punter?' and if the answer is no, then I'm suddenly fully booked. You can turn any of them down for any reason you want and also for no reason at all