I'm going to be starting the very same sort of thing soon. The work I do is related to the course I'm going to be doing so my main motivation is being better at my job, and hopefully ultimately have a better salary
I'm a web developer, so learning more on this and increasing my skills is quite interesting.
The only advice I can give you is that you've got to really want to do it. If you cannot motivate yourself, then either you are unhappy in your job, or you're in the wrong profession.