Everything stems from your beliefs. If you don't believe magick can happen - it wont. When you believe in what you are doing, can see it as your reality and then combine that with a powerful spell, it will happen!
You just don't go out there and wave a real or imaginary wand and it all happens. You don't just say words and expect a chariot to draw up outside your house and have it handed to you on a silver platter. You have to focus on what is is you want, imagining that you have it already.