If you consistently do the same exercise at the same rate, your body adjusts and becomes more efficient. On the same note, try interval training. Work out at a moderate pace, one that allows you to carry on a conversation. Then for 5 or 10 minutes, spike it to a level where you break a good sweat and find it difficult to talk. Slow it down again for 10 minutes, then increase the intensity.
Strength training is a good way to burn more fat.
That's because muscle burns more calories, even at rest. For every extra pound of muscle you add, you burn 30 to 40 more calories a day. Eat earlier in the day. If you skip meals, you'll just pig out later when your metabolism is slowing down for the day. Try and make breakfast and lunch your biggest meals, and don't go under 1,400 calories a day.