Well, since you are a beginner, I suggest you start off simple.
For now, use the 'hold all' feature in which all your joints are in the "Hold" position.
This can be done by pressing the 'c' key on your key board while in single player or multiplayer. From there, I suggest you see what each joint does, one joint at a time. Once you understand how all the joints affect your Tori, you can then use multiple joints at once to get your Tori moving. Just play around with it, and see what you come up with. While doing this, make sure you are taking advantage of the ghost feature. Press the 'g' key on your keyboard to toggle both ghosts on and off. Start making joint changes and come up with a good opening move that you think will be able to develop into an even better move.
The best advice I can really give you is to play, play, play.