I made a list of what needed to be learned for each subject the first day of each class, then divided it up. For example, when doing gross anatomy, I'd make a list like 1.arteries of upper extremity, then subdivide like "muscles supplied", "collateral circulation patterns", etc. Then I'd put the items onto a little calendar, so for the rest of the course, after that 20-30 minutes of planning on the first day, I'd know what I need to studying. As I realized things that I didn't think of, as the course went on, I added them to the list.
After having a list, it's easy. Each day, sit down, and LEARN what is on the schedule for that day. Don't lay down on the couch and "study" it, learn actively. If I thought I wasn't paying attention, I would close the book and take out a blank piece of paper and start writing down or drawing whatever I was supposed to have learned, then I'd check it. This method helped me to not waste time. I think most people have had one of those days where you spend all day studying, then at the end of the day aren't sure what you retained. In med school, you don't have that kind of time.
The last thing I'd do at the end of each day is try to recall what I learned. I'd either use a blank chalkboard and write it down, quiz myself with board review books or old tests, doing the questions on the subject I learned, use a blank piece of paper, etc. On the test, you need to be able to recall things, so if I could do at the end of the day what I needed to do on the test, then I was done studying for the day.
I'm not sure if I'm a "gunner", but I did very well in my classes and I'm in at least the top 15% (we're told whether or not we're in the top 15% after first year, but not given our rank).
Good luck to you, like everyone keeps saying, the important thing is to find ot what works for you. There are other people in my class who did awesome, but I can't learn by studying the way that they study. My advice is to do a recall test of some sorts when you try a new way of studying, to see if you are retaining. I use flashcards when I find I'm just not retaining something.