I had been meaning to do this for a long time.
I'm one of those 'bottled water is a joke' nut jobs, so I got a vintage canteen online last year. Now, the sleeve it came in was grimy, and not at all fashion forward, so I didn't use it, and the aluminum canteen just kept banging around in my bag. SO! I finally got around to whipping up a pattern, and making a new, more chic sleeve for my water repository.