It's a bit more than a foot long and fairly easy to build.
You can download the pattern for free here.
PSA: I've seen several people make this out of plain white printer paper. Do not do this. It will look terrible. Go to your local craft store and buy some colored cardstock instead.
PSA#2: There's a number of etsy stores selling this pattern. I'm not associated with any of them. If you pay someone to mail you a pre-cut pattern that's fine but none of the money reaches me. (If you pay someone to email you the pdf then you're an idiot)