1. Stick to a regular skin care routine. I'm not a dermatologist, so I can't tell you why this works, only that it does. I used to only wash my face when I broke out, but now I wash it every morning and night, and that has made a world of difference.
2. If you use a powerful cleanser like Proactiv (which has done wonders for me), make sure you only use it once a day. Your skin tends to build up immunity quickly to powerful cleansers, which is why they can stop working after only a few months. Using these just once a day can prevent this immunity. For your second wash, use a milder cleanser. I use the Neutrogena oil free acne wash in the mornings, and I love it!
3. Change your pillowcase once a week. This may add up to some extra laundry, but your face will thank you! Tons of bacteria and oils build up and rub of on your pillowcase when you sleep, and frequently changing it will help keep these harmful substances out of your pores.
4. After you shower, never dry your hair before you dry your face. Residue from your conditioner will rub off on your towel and, eventually, your face. The best thing to do would be to use a different towel to dry your hair and the rest of your body, but that will add tons to your laundry load.
5. Always always ALWAYS take off your makeup before you go to bed. This should be a given, but I thought I should reiterate it.
As always, I hope this was helpful, and stay classy, America!