I made an ottoman cover using the granny stripe(http://attic24.typepad.com/weblog/granny-stripe.html) for the sides and the Red Heart Granny Blues Lapghan pattern for the top,changing colors every two rows.
Using an I hook, I chained 39 for the sides. This took some trial and error to determine the correct size for my ottoman.
I did a single crochet edge and joined the pieces with a single crochet.
It ended up a little bigger than I wanted so you may want to allow for that.