Need to lose 5 inches off my waist fast?

I'm 22 years old 6'1" and about 257. I have a 45 inch waist. I need to shrink that down to atleast 40 in order to join the army. I only have about a month and a half to do so. I know that it's not the healthiest idea but nevertheless it needs to be done. For the past couple weeks I've been drinking a protein shake for breakfast and lunch, and I have a normal dinner but in smaller portions my wife makes (so I'm not cheating). I'm now beginning to jog 2 miles a day (1 in the morning and 1 after work) I don't eat fast food (hardly eat out at all) or drink regular sodas. I think I've lost about 5 pounds but I wanna know how I can speed things up?