The 2 most common setups are Mode 1 and Mode 2 (see attached diagrams. I've also included a diagram showing Modes 3 & 4 as reference.). In the US most people will use Mode 2, but in other parts of the world Mode 1 is more common. A lot of your setup will depend on the radio, and where the throttle control is located. If it's on the right use Mode 1, and if it's on the left use Mode 2. Another huge determining factor is going to be your instructor and what they fly. The best advice I can recommend is find and instructor and ask them to help you get your radio setup.

Hope this helps

Ken