Histo (and pathology) are all about pattern recognition. Looking at the series of slides over and over again is really helpful.
If your slides are on the computer, you can put together huge powerpoint presentations (with the names left off, obviously) and quiz yourself with them. There are online histo quizzes somewhere - those were helpful too.
Definately look at the slides over and over again. I found that using note cards and drawing what the slide looked like to me was really helpful as well.
I used a web based microscope, tutorialish program. This post is not very helpful but I just want to iterate that I loved histo. Drawing no way. See if you can find ways to quiz yourself. My program had it built in fortunately and I learned it very well that way.