It's easy, and good for you! Learn how here.
Step 1: Hold a toothbrush, bristles facing up.
Step 2: Add a small amount (about half of a dime's worth) of toothpaste on the bristles of the brush
Step 3. Rub the bristles with toothpaste along your teeth with light pressure hitting all of the surfaces of all of your teeth, even the ones in the back! *Be sure not to swallow any of the tooth paste.
Step 4: Spit out the tooth paste in a sink, and rinse out your mouth with water. Again do not swallow the rinsing liquid.
You did it!