a soft cuddly blanket with enough fabric to fit all the pattern pieces onto. I found that a King Size blanket will give you around 1 and 1/2 bear suits. A queen size is about right. You might need two twin sized blankets to do one. My favorite blanket in the whole world are these fluffy microplush blankets from Target: The Threshold Fuzzy Blanket
. (http://www.target.com/p/threshold-fuzzy-blanket/-/A-14517614) They are the softest most wonderful blankets when they are new. My only complaint about them is they get nappy the more you wash them and they eventually lose the fluffiness of a new one. But they are still warm as can be. They usually go on sale in the fall for around $40 a piece, but by spring, they are often discounted down to $25. So that is the best time to buy them.
The longest dual separating zipper you can find. I've been using 36" dual separating parka zippers. However, the longer the better. If you can get a zipper that goes all the way around, that means you can get back rubs without removing your bear suit!
A pattern for a big roomy jumper with a front zipper. I took a stab at drafting my own pattern for this project to ensure that it is a 100% original design and I'm including that pattern here. However, I'm happier generally with the pattern I bought from McCalls, number M6106
(http://mccallpattern.mccall.com/m6106-products-10917.php?page_id=915) which has raglan sleeves and is one size fits all. If you plan to do this project I recommend the commercial pattern over this one I made.