Knock down the carbs (below 50 grams per day is ideal) and start working out regularly. Pick workouts and activities you like to do - there is a higher likelihood you will stick with it.
a healthy and safe way?
do it slowly
do it smart
translated, this means choosing lower (and healthier) fat foods, eating more fruits and vegetables, keeping your fiber high and your excess sugar low, getting enough (but not too much!) calcium and caring MORE about the ingredients than whether they have diet claims on the label (low carb! fat free! sugar free! high in Vit C!.... all that jazz is NOT what is important).
and above all, making sure you are exercising regularly in a healthy, balanced way. this means some resistance training and/or weight lifting, some cardio, and always working to strengthen and increase your flexibility and muscle tone. a leaner body burns more energy than a flabby body, so working out gives you a double benefit.