
Learn proper portion size. To avoid eating too much of even the healthiest foods, keep track of how much you're eating. For most people, meat servings should be about the size of a deck of cards and other servings vary by the type of food.
Keep healthy snacks around. It's easy to eat healthy if you keep the Cheetos at bay and stock your dorm room with fruits and other healthy snacks. You'll be more likely to reach for these than junk food if you keep them nearby or in your backpack
Drink moderately. While college students are known for their partying, you can still have a good time without consuming all the calories that come along with binging on beer, plus you'll avoid the hangovers and other negative effects. Drink in moderation and you can have a good time without hurting your health.
Don't fight stress by eating. It can be tempting to reach for a bag of chips or some cookies when you're stressed out about an impending exam. Eating won't help your stress go away, so avoid filling up on snacks. Try working out or taking a break instead.
Make it convenient to eat right. Don't make it hard for yourself to eat right. Buy healthy foods and stock your fridge and room with them to ensure they're the first things at hand when you get hungry.
Take advantage of open spaces. Most colleges are equipped with large grassy quads or arboretums with trails you can walk on. Take advantage of these spaces to take hikes, play frisbee or just walk around
Take a nap. If you have the time during the day, a short nap can do wonders for your energy levels. Just make sure not to nap too close to bedtime or for too long, and a nap will do your body good.
Don't work in bed. Working in bed can make getting to sleep harder. Keep your work space separate from your sleep space to keep insomnia at bay.
Understand that lack of sleep can have a big impact. Lack of sleep doesn't just make you cranky, it can also reduce your ability to concentrate and to excel at class, so try to get as much sleep as you need.
Avoid ill friends. If your friend is sick, try to avoid spending too much time around them. While bringing soup or medications won't hurt, touching ill friends and their stuff can increase your chances of getting sick yourself
Know the signs of depression. It can be hard to differentiate a simple slump from serious depression so learn the signs of depression not only for your own benefit but for the benefit of your friends as well