How to lose about 20 pounds?

I am about 5' 5'', I weigh about 125 and would love to get down to 105. the difference it would bring to my mid section would be amazing. That is really my only trouble spot is my stomach and love handles. Please help... good exercises and particular foods to stick to? I am 18 and out of college for the summer. I make a fresh fruit smoothie every morning with yogurt oj and frozen fresh fruits. I need more though since I'm not seeing results!