How do you skateboard?
If you are a beginner, I would start off by taking a few lessons. What you have to do is stand on it and push and you're off! Remember to keep your balance for turns. Good luck!
Just step on with one foot and push off with the other keeping balance and that's all there is to it. Once you have gained the confidence to extend your ability you can start doing tricks by flipping and jumping. Remember to wear pads and a helmet to protect yourself from all the falls that will inevitably happen though.