I had bought some memo pads before the holidays, in case any small children needed entertaining with coloring and stickers, so I made the case to fit them: about a half inch wider, and probably somewhat more than a half inch taller, times two.
The pocket is a piece of stiff white fabric with each edge folded in a half inch, and the open edge tucked under again (so it is folded down by 1/4″ twice). I stitched very close to the raw edges on the sides and bottom to keep the seam allowance fabric from scrunching when the memo pad was inserted.
The cover was a little flimsy, since it was just thin felt, so later on I decided to add a small pocket to it mostly to stiffen it up. I then had a bunch of uneven stitch lines, so I thought I needed either more stitching, or less. Since less would have been difficult, I went around with a zigzag. I like the result.