I talk to a LOT of people who want better jobs. A lot of them never consider finding ways to start doing the job they want before they get it.
An article on how to prepare now to get a job when you graduate got me thinking. You need to do the same thing to progress in your career anywhere. The best way to get a promotion is to start picking up parts of the job you want to do. Help the current job holder when you can. Train people to do YOUR job. Volunteer somewhere to do the job you want.
The real trick is to get experience before you get the job. Then you are the natural person to hire.