Hatching out some rough ideas. Sorry about my handwriting! I don’t want to start cutting out fabric until the laptop is in my hands, just so I can adjust sizing. Especially since I’m going to have to add a little for the padding.
I’m rounding up just to give leeway for mistakes or future laptop skins or fabric thickness. It’s a lot easier to include extra fabric in the seam allowance than add fabric if it’s too small.
Debating between a flap and/or zipper - I like being able to fold it out but finding a zipper that would fit might be tricky.