Yes, it's not hard at ALL! If you can do k1p1 ribbing you can double knit. Promise!!! Have you seen amy's video? It's on THIS
page. The directions in the pattern are very clear, so I'm sure you won't have a problem.
I ended up not using stash yarn
I had to buy some "emergency" knitting supplies since I had a meeting after school today, and I forgot to bring my knitting. I noticed in the pattern that it didn't specify doubling the yarn, but I doubled it anyway... which probablly means I didn't buy enough. I'm using cascade 220 in hot pink and navy blue for the bottom, and I *think* have have enough "other" cascade 220 hot pink and black for the sides. (from an abandoned project).