When you start Moto X you are given a menu for Play, Practice, How to Play, High Scores and Options. The game is pretty straight forward to play, although it does take considerable practice to master the bike and perform tricks (flips) while riding. Press the right side of the screen to accelerate, the left side to slow (never used it) and then tild your device to lean forward or backward on the bike. You can also adjust things like tilt sensitivity (leaning forward/backward), and sound effect volumes under the options menu.
The main trick of the game is learning how to lean and when to accelerate. Leaning too far forward or backward and you'll assuredly wind up in a wreck. However, getting the knack of this action is also what makes the game fun and enjoyable as it opens you up to tricks as you jump over the terrain. This is also where the bulk of the challenge of the game is because when the terrain changes you must know how to lean in order to effectively navigate over it. Leaning backward while jumping can also allow to do a back flip, likewise, leaning forward and you can go all the way around on certain jumps as well.