I'm not really sure if this lid is really "finished." I painted a thick layer of sodium silicate on the garbage can lid and then placed the round piece of fiber into the lid and used a rubber kitchen spatula to kind of tuck in the edges.
Once I fire-up the kiln for the first time I'll find out whether or not I need to add any additional buttons to hold the fiber in place. If any additional buttons are needed, I'll add them. Each button takes just a few minutes to install.