Originally Posted by np3
I'm not sure what you "sleeve" pattern looks like. I usually make a kind of pocket with a flap. They are more forgiving with the size. I can't find any picture of them right now.
The pattern I'm using also has a flap with hook and loop tape. My instructions were to measure length and width, then add the height to it. That works for your own personal laptop, but I'm trying to make several in a generic size.