The Magician is a tarot card that reminds us about the simplest way we undermine ourselves in our daily lives: forgetting our power. Often the card appears to simply say, "You hold ALL the power, what are you waiting for?"
We forget our skills. We forget the power of our intention. We forget that we are connected to creation, and therefore are co-creators in this world.
Sometimes we need someone else or a situation to trigger us into remembering everything we've learned and all of the abilities we have. Think of your first job. Everything you absorbed and cultivated there prepared you to move on to another one, where you were probably even better, so prepared and clear on how to act and take action. You simply know how to be in your power at a certain point, even in new situations, without even thinking about it.
What have you forgotten that you can do? Recall what it is, and recall your powers to you. Go out there and do it! :)