Medical Insurance. If you don't have medical insurance there's no point in reading any further. Everyone I've ever known who rides motocross has taken that ride to the hospital at some point. A common knee injury can cost $40,000. Don't bankrupt yourself and your parents. Don't ride unless you have medical insurance. Physical Condition. Are you physically ready to ride? Motocross is the single most physical sport there is. Most of the muscles you'll need can be developed with lots of seat time but you'll need a decent base layer of conditioning. I'd hit the gym and start with some cardio, then maybe add in some cardio after that. Motocross Gear. There is a simple rule. Dress for the crash not the ride. You can start with used gear off eBay if you have to but do not skimp here. If you're buying used hit your local shop and try stuff on to get your sizes right first. Most shops have closeouts too at greatly reduced prices so start there. You're going to need just about everything pictured below which includes helmet, jersey, mx pants, gloves, goggles, knee braces, chest protector, boots, and a large mx gear bag to keep it all together. Keep everything in your gear bag at all times. Duplicate things if you can. When you wash something it goes straight back in to the gear bag. There's nothing worse than driving two hours and realizing you've forgotten your helmet.