How can i lose belly fat?

I weigh about 142.5. I want to lose at least 40 pounds it because i know its all of the belly fat i have. I need to lose those 40 pounds before July 16th!, so if it is possible can you give me some ideas?!
PS- starting tomorrow, i will play wii fit for about 30-40 minutes, then run on the treadmill about an hour, but thats all i have—anything else?!