Here is a link to an amazing website that I follow daily. There is a variety of ways to make this great tasting green smoothie, you can even add a whole food protein source, which is included.
If you need it sweet to get used to it, add raw honey to taste, about 1 tbs. to begin with, then decrease as you get used to it. The honey will add extra health benefits as well.
I am working on gathering a variety of smoothie recipes, look out for it.