Upholstery and Fabrics - replacing padding around springs of patio glider cushion

I am making a new vinyl cover for a very old patio glider seat cushion. Making the actual cover is no problem for me, I'm using the old cover as a pattern. But the springs inside the cushion were wrapped with fabric and padding that is so old and disintegrated that I don't have a clue what to replace it with. Can someone explain to me what to use to cover/wrap/cushion the springs with, how thick to layer the materials and if it is necessary to attach the materials to the springs-how to do that. Thank you.

There's a lot involved in doing this and not an easy task and may not be a DIY job. I wouldn't even know where to begin to explain. I don't do this personally, and I would send it to a professional upholster. However, if you do want to attempt it, I'd suggest buying a good book such as Singer's Basic Upholstery book which has very good instructions and lots of pics. I would also go to an upholstery shop to buy the things needed because I don't know where else you could get all the padding, horse hair, batting and other things needed.
Another option is to make a new cushion altogether using dacron wrapped foam, and again you'd need to buy this from an upholstery shop.

My guess would be that you could cushion the springs with foam and wrap with quilt batting. Thickness would be determined by the size of the upholstery you have removed--4", 6" or whatever.