Since June I have managed to lose 6 kgs (started at 85kgs, am now 79kg) by adjusting my diet and by hitting the weights.
My breakfast and evening meals consist of smoothies containing Whey Protein, Berries (the frozen UNSWEETENED one you can get at Asdas), Low fat yoghurt, Almonds, Flaxseed and ice cubes. These are really filling and quit tasty. You will lose more weight consuming food in a liquid form that you will in a solid form. Dont ask me why but it is a fact.
The best way to get your body to burn off fat is by building muscle (hence the whey protein). The best way to do this is to hit the weights. Join a gym if you can, if not go and buy yourself some basic equipment. I try to do at least 20 minutes a day, bicep curls, bench press, military press, chin ups etc etc.
You should also try and avoid consuming carbs after 6pm.
The first four weeks I didnt lose anything but after that the weight just fell off me. I'm hoping to get down to 75kgs which is what I was before I turned 30.
I can really recommend the following. It's only a fiver and it contains some really great tips.