I’d like to know this as well if anyone is kind enough to share.

Make that a third person interested. Maybe this would be a good article for the home page @Nadeem Muaddi

depends on your application and I can only speak on behalf of the ones i know..

1-Wood base- cut foam and pull tether down to staple

2-obviously you could liquid listing (glue it down inside or to the foam)

3- Or you can sew the listings in the seats, use a long needle and sink it down through the foam and tie on the backside. Channeling the foam out will make the listing pull inside more.

Plastic zip ties,can be pulled down through slits in the foam. Build up or remove foam to achieve the desired shape.

I like to channel the foam with a trim router and a 1/2” wide cutting bit, then use Velcro like many modern seats