If you are a full-time student, then you have to treat it like a job/investment. After all, you are paying for it. Even if you are on scholarship, you earned it and are spending it.
I like tangibles, so here is my list of tangibles for full-timers...
1. Treat the school day like a workday. 8-5 with a lunch break. Stay away from "home." The temptation for a nap or a short break is too easy. Sometimes your day might run until 6 pm, but that is still fine. Work during the day, and enjoy your evenings. Some people are night owls, but you are just going to have to get over that. You are in school to get into a system, so you might as well get started now.
2. Be realistic. Many people take on a course load that is too much. Some people can take 25hrs a semester and excel. However, some people can't, especially those with other interests beyond school. Take an appropriate course load so you can be successful; you've got the time.
3. Set Goals. Don't study for the pure sake of studying. For example, before you even start your study session, tell yourself what pages you are going to cover, and don't leave until those pages are done. Again, treat it like work. If 5pm rolls around and you aren't done (homework), you have to bite the bullet and keep going until it is done.
4. Never miss class. Again, treat it like work. If you miss work, you would get reprimanded, or even fired. Treat class the same way. Also, simply being exposed to the material will help. Sometimes there are good reasons to miss a class....being sick is not one of them.
5. Get Organized. Even if you have impeccable memorization, getting an organizer is just good practice. It helps eliminate procrastinatio n. It'll also give you a venue to write down your goals. It'll also list your free hours. Organizing your free hours is just as important as your To-Do List. It'll also help you budget your money. The worst thing for a student is to be poor.
6. Network. This isn't really a study habit, but this is the one thing many people fail to do while in school. For many people, professional success has more to do with networking skills than actual skills. Also, networking keep your mind focused on your class material. If you find yourself into a study group, even better.
7. Exercise. People may think this is a weird one, but a healthy body actually helps improves brain functions. Sure, this isn't true for everyone. However, it helps a lot of people. Also, it gives your brain a chance to rest. Talk about rest....
8. Sleep. Did you know that driving sleep deprived is worse than driving drunk? The mind operates best with optimal sleep. Once again, find out how many hours you need, and fit that into the schedule.
As for part time students....Go od luck. Everyone is different.