This question has been made several times over the past month, so I decided to make a sticky about it. This is the answer of how you should proceed to lose fat and keep on your muscles. This is basic advice, but a lot of people don't know the basics:
Find out how many calories you need to maintain your current bodyweight, then subtract 500 calories from that and spread it over 6 meals. For every meal get a lean protein with very low glycemic carbs and vegetables. The protein is important because it furthers decreases the glycemic load of the carbs, and spares muscle which keeps your metabolism high. The vegetables are important for G.I health, vitamin/minerals and antioxidants and keeps you full. Do one hour of low-intensity aerobics first thing in the morning on an empty stomach, or if you feel light-headed, do it in the afternoon. It is very important to do your weight training, as the more muscle you have the more calories you'll burn while resting.
Finding out how many calories you need to maintain your current bodyweight can be done in two manners. You can do it professionally with a calorimeter, which is impractical, or write down everything you eat for three days, add up the calories by checking on calorie tabs, which are easily available, then divide by three. This will give you an idea of your daily calorie intake. Proceed as elucidated above.
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