This is what I have made today. I will add an applique on the front and a button.
Opened.
This is what I used. You need a hard cover that is strong but firm. I used this folder because you can cut it with a Stanley knife. The fabric I used has give all round to be able to insert the hard inserts.
This is the method I used. 2 pieces of hard card, One for the outside and one for the appliance to sit in. The smaller piece is the same size as the appliance, the larger piece is 1/4 bigger all round plus depth of appliance. Make score lines on the depth so that it can be closed. Make sure you do not cut it all the way through.
This is the outside piece. Trace around the card onto your fabric doubled, add elastic to sew into the seam and mark a cross for cutting the fabric for turning on one side only where the elastic will then be on the back of it. This is why you need fabric with a little give.
This is the inner piece, where the appliance will be sitting on it snugly held with the elastic. Sandwiched between the two layers of fabric is the elastic that will hold your equipment in place. Sew all around, snip corners and even it all up. Cut a cross in the fabric on one side only for turning.
Turn it right sides out, insert your card and hot glue the cross closed. It will not be seen.
Seen from the front.
Hot glue the insert to the main body.
This is the finished product open
Finished product closed.
I have not given measurements as this way you can make it for whatever you wish .