Lets say you have a solid purple tutu and you are tying pink pieces on the bottom to make it puff more like a petti tutu tie one end of the pink and one end of the purple once then knot again with both purples, this secures the ends. I don't know if I explained it right or not. Is this what you meant? http://www.wildflowersandwhimsy.com/2010/11/petti-tutu-tutorial/
<--- this is the pattern I followed.