Wow . . . there are a lot of negative responses here. What's up with that?
First thing you want to do is to take some safety precautions. This isn't just about BDSM- it's about meeting people on the Internet, even people who seem nice and normal. Meeting at the mall is a good thing- lots of people around. You are also going to want to tell a friend where you're going and have him or her checking in with you (with the instructions to contact the police if you don't check in or respond to his/her calls), and have a pre-agreed upon word that you can use to indicate that there's a problem, should there be one. You want somebody out there to have information on this Master- like full name, address, and phone number. Definitely not just a user name. He should be willing to give this information to you- if he's not, I would ask myself why, and be wary.
I know that all of this seems like a hassle, but quite honestly, sometimes terrible things happen. If you want to meet people you know from the Internet (which is what I'm assuming here), you need to take precautions.
As for knowing what's going to happen on the first encounter . . . I can't really say. There's no standard manual here; everybody operates differently. You'll probably be sizing one another up, seeing if the person you've met online/over the phone jells with what you see before you. You'll probably talk about what you want in your relationship and what your limits and requirements are. There might be a bit of flirting. But that's really all a first "date" should be- talk and discussion.
Surprise? It might be a nice little gift. It might be something as forward as a collar (which would be *quite* forward, and possibly a warning that he's not for real/not to be trusted). I just can't say.
Just remember to be careful, keep your wits about you, get references on this guy if possible, and to always stand firm in your limits, what you want, and in trusting your gut. There are lots of good BDSM Masters out there, and lots of posers, losers, and even dangerous guys. And even if they're good guys, there are still lots of people out there with whom you might not connect, or from whom you might want different things. Just because you're a submissive does not mean that you need to acquiesce to any and all demands. I know what it's like to feel a little desperate, to latch onto the first (and oftentimes only) person who pops up that seems even close to what you want. But don't compromise yourself if you start to feel like something's "off".
Good luck.
