If you mean the simulator and the real controlling that comes later on, it's a lot to do with your own skills - each type of controlling requires different skills although it's hard to say if you have them or not until you try. Don't separate out the theory and the sim too much - they go hand in hand and if you don't know your theory, it doesn't matter how good your R/T is, you still won't be able to tell the planes what to do!