If you desire a sweeter shake, add stevia -- a natural, non-calorie herb.
Other ingredients can be added such as frozen strawberries and blueberries, which are both rich in antioxidants. You can also add half a banana to provide carbs, potassium and help it taste great. Be aware that fruit also contains carbs. If you want to limit your carb intake, you can omit these from the shake.
Mix all shake ingredients into 10-12 ounces of water, blend and enjoy.