I second all of Winner's advice except for practicing in front of a mirror. I found that to be super distracting. Instead, try practicing in front of an animal if possible. If you have a dog, that is ideal. Dogs are attentive and non-judgemental. But other animals will work too. They just won't be as attentive as a dog.
If no animals, try giving it to toys; action figures, dolls, stuffed animals. They are to simulate an audience.