My jig of choice is a board with a piece cut on the band saw that
matches the inside opening of the pneumatic.  It is just deep enough
for the leaves of the pneumatic to lip over.  It sort of looks like
the letter "T".

I cover the long side first.  Move on to the next one and so on.  Then
I then go back and cover the end and the last long side.  I let them
dry and then I do the hinge end.  Make sure you put a felt punching
inside.  I do the hinges first and let them dry.

I use pillow ticking for the hinge and for the felt stop I use punch
spring rail cloth cut with an arch punch.  I use the nylon pneumatic
cloth now since the rubber cloth seems to have a short life span.

Don Teach
Shreveport, Louisiana