Build up the gear gradually. Talk to people onsite about what they have, what they tried and you'll soon build up a profile of the things to do and the things to avoid and why. People on site are always more than happy to tell you about their gear choices and its one of the best places to see what can be bought and get an idea of what stuff is kind of rubbish or caused problems.
Early on one of the first things I bought was a sling, because my arms were killing me after carrying a heavy gun around all day. Bought a single point sling and it worked great in the CQB site I was playing at. Then I moved into woodland and big area combat in general and suddenly the sling was killing my back. Its hard to walk with a low hanging single point sling, so now I have moved to a two point to one point adjustable sling.
Its that sort of advice you'll get in little snippets and so rather than buying it all at once do it in snippets as and when you need it want it/can afford it. It'll save you money in the end.
Got yourself a nice starter gun
