If you enjoy watching MMA, then perhaps you think you've got what it takes.
1. You'll need a good overall fitness level, and if you're not used to exercising, then perhaps you'd be better off with a few months of general fitness training, so that you are in good physical condition to start off with.
2. You'll need to stick to a healthy diet to ensure that your body gets all the nutrition it needs to repair itself after the grueling workouts you're giving it. Remember that your body is like a car, it relies on the right sort of fuel to keep it performing well
3. Suppleness is important too. You're going to need to able to stretch and get used to having your limbs in strange positions as you learn submission holds. Also, the more supple you are, the faster and stronger your punches and kicks can be.