Here are the instructions from Cozy:
What to do:
Step One: Browse through our collection of fabric by the yard (click on Step 1). Then purchase 10 yards of regularly priced fabric... you can mix and match fabrics, but you have to do it in one yard increments and they must all be regularly priced.
Step Two: pick out your 10 FREE yards from our specialty marked online fabric (click on Step 2). Quick Tip... all of the specially marked fabrics start with "Get FREE" and are in the "Sale Category". We have them at a price of just a penny, but we'll zero them out when we ring it!
You may mix and match, but must get one yard minimum and one yard increments per fabric (both purchased and free).