I am assuming you are interested in motorcross racing, if not most of the stuff will apply anyways
The first thing you want to work on is holeshots. Mastering this will allow you to begin building the foundation of your riding. I am not talking about simply getting the holeshot at a start. What I am talking about is learning to holeshot your bike. Find a jump, jump it. Now move closer to the jump, stop and then jump it. Keep moving closer and closer until you can jump the jump when your are right on it. What this is doing is teaching you to holeshot out of corners and other tight areas. Ever wonder how the pros get such distance on jumps when there doesn't seem to be much take off? This is how. What you have to do is get the r's up, slip the clutch, but not all the way, keep the bike hungry while giving it plenty of throttle and you will launch like you wouldn't believe. They make beefed up clutches for a reason. You want to get use to using the clutch to perform all sorts of things, such as holeshots, brakeing, and guiding the bike. In other words, you know how when you take off on your bike and you get the arm pull from the torque?, you want to get that as fast as possible to get you up to speed as fast as possible, and have that torque launch you over the jump. Once you have mastered how to get your bike up to speed the fastest way possible,asw ell as using the speed and torgue, work on controling your bike in the air and on your landings. I'm sure you're probably aware of how to guide your bike in the air using the brake, throttle, and body english, but practice landing in the attack position and learn to race out of landings. A lot of guys lose a lot of time by the way they land, land on the gas! Stay lose and pay attention to were your body is. And remember to breathe and stay relaxed, sing a song while you're riding, it helps you breathe and stay relaxed. For corners, the guy above pretty much covered it. Just remember to break late and gas early. Practice diving into tight corners and breaking as late as your balls will alow you, then gas it! Remeber there is no coasting, you're either on the gas or on the brake. Whoops, you need to just go out and do them. You can double, tripple, or skim them, depends on what you are comfortable doing. Remember, the faster you go the better they are, usually, just remeber to let the bike move underneath you and allow your suspension to work it's magic.
As far as your bike is concerned, mx races are brutal on bikes. Keep it lubed, tuned, and the airfilter clean. First off, buy nerf bars, good handle bars, and a kill switch. When you get more comfortable and decide that this is what you want to do, buy a swingarm, shocks, a-arms, exhaust, axle, and beedlocks and a gusset kit. That should get you started.
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