I bought the raw material from a fabric store... $6.00 a yard...
My buddies wife cut the circle and sewed it...
If you don't have a handy seamstress,... you could just use staples, or hooks, or velcro,... er' sumtin'?... (it's strecthy, so it's pretty forgiving, fit wise)...
It's lightly foam backed, too... so there's some cushion as well...

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