Do you know of someone who is doing what you dream of? Are there any role models, mentors, or coaches you can learn from? Study what others have done and ask them questions if you have the opportunity. Now that you already know what you want, you just need to figure out exactly how to get it!
While you're keeping your eye on the prize, you might be taking too much in at once. You also may be trying to accomplish too much too fast. Break down your dream goal into smaller mini-goals. Once you have a simplified plan in place, attack each mini-goal with your full attention and you'll be chipping away slowly, but surely at your dream goal!
It always helps if you're seen as the type of person that will go the extra mile. If there's a specific dream job that you're interviewing for, study the objectives and duties of the job carefully. Make sure you have the qualities and skill set they're looking for, and if you don't, show that you're willing to take the initiative to acquire them.
This is where the vast majority of people drop out.
All talk. No action.
Don't be one of them.
There may be a number of things that are holding you back from truly going for your dream job. Identify these causes and eliminate them. What are you afraid of? What is in the way of you and your dreams?