Cardio vascular exercises are a good way to get rid of the fat in the body. You cannot get rid of hip fat specifically, the only option you have is to work towards getting rid of the fat in all parts of the body and there by remove fat in the thighs. You must exercise around 45 minutes every day, and concentrate on the treadmill and cycle. You can also combine cardio work with other strength training exercises. Remember that this will take you at least a few months and you will see changes after a couple of months. Cheers