It's been several years since I've known I need to have my batteries sorted, like visibly sorted. I've had pouches, but without writing and I never knew which one contained what.
I cut out rectangles and serged the edges. I made some tests and finally I used two layers of stiff cotton canvas under the embroidery. I made a sample of each writing and measured its length to know where to place it.
I sewed the edges, one of them not up to the very top, leaving a gap for cord fastening. I sewed the tunnel and that's it.
I was annoyed how it keeps opening, so I made a knot which slides on the cord and keeps the pouch closed.