Yes, you can lose weight if you follow a well planned diet with discipline in your lifestyle. For a diabetic it is best advised to have a diet planned as per the sugar levels, lifestyle and history.
Though you can follow some guidelines -
have small frequent meals.
Do not fast for long hours.
Avoid a very heavy meal at one time.
Avoid fruit juices, aerated drinks or sugarcane juice, honey, jaggery or sugar.
Avoid junk foods.
Exercise and stay active.
Do not attempt to try out too many remedies as you could go into hypoglycaemia.
Sleep well. It's all a matter of discipline.