Reduce the sugar and dairy in your diet. Yes that wonderful sweet sugar can increase the breakouts and Dairy can cause problems if you're lactose intolerant or have an undiagnosed casein intolerance or allergy. Acne is actually a inflammatory and hormonal response in your skin, but reducing refined sugar and dairy will help. Once your diet is balanced your skin will clear. It's one of the side benefits.
I'm 30 and have fought 'problem' skin for at least half my life. I see a clinical esthetician regularly for 6 years now, and through internal as well as external changes, the difference is remarkable.
However, I have been on the diet for a few months now (she sees me every 6 weeks), and just a couple weeks ago, she said to make sure to keep doing whatever I was doing because my face was the most wonderful it's ever been!! And the cycle diet is the only thing new and different in my regiment. So, yay!