Step 3: Glue Fabric to Foam Core Board
Spray about an inch-wide strip of 3M Super 77 adhesive at the very bottom of the short edge of one side of the foam core board.
Gently wrap the fabric around the edge (you may need to wait a minute or so until the adhesive becomes tacky).
Run your finger along the edge to smooth the fabric out.
Once the edge is well-adhered, flip the whole thing over and spray adhesive all over the foam core board. Smooth out the fabric so it is centered, repositioning if necessary.
Flip the foam core board back over and spray one of the long edges with adhesive.
Fold the corners as illustrated below, and then fold the long edge over the board. Remember to run your finger along to smooth out the fabric.
Finish folding in the remaining short edge and long edge.