Sorry to bump this thread but I've just recently started to lose some body fat and I can give you some tips that have worked for me.
Do HIIT (High Intensity Interval Training). It a cardio technique that burns calories up to 24 hours after your work out. What it does is that it doesn't let your heart get use to a steady heart rate. If you jog at a certain speed for an hour your heart would get use to it, you'll still burn calories but there is another way thats better. With HIIT, you jog for one minute, and sprint for a minute, then back to jogging for a minute. This helps you burn more calories and also preserve more muscle. You can also do HIIT on anything that involves cardio, like stairs (run up two-three flights as fast as possible etc), bikes, and also jumping (jump up and touch something 10 times, rest for 30 seconds, go at it again for 15 minutes).
I've been doing HIIT and lost 2 pounds a week. A good diet helps the most though, if you can't give up coke, drink Coke Zero which tastes just like regular coke. Sugar fucks you up the most I've noticed, once I stopped drinking soft drinks I felt way better and lost more weight.