How do you study? I need to study for a promotional exam.?

I need to study for a test at work but having a lack of motivation in doing so. Every time I begin studying I find myself getting sleepy or my mind drifts off to other things. Everything is distracting me. I can read a page and not remember what it was about. I read the same sentence over and over sometimes. I find it possible to read and think about other things at the same time, or perhaps my eyes scan the lines and not read them. I need a good study habit. I need to re-learn how to retain information. The books I have to read are very dry and boring, nothing fun about it. How do you learn things that are not interesting to read? I have 1 month til test time. I need your help. I need to study, remember and retain what I've read. How do I do that. I used to be able to but not anymore. Surely there are tricks or tips to studying. I've tried to scan over a paragraph and pick out the highlights, but not any better. I read about as fast as I talk, reading every word, HELP