How to soften an upholstered chair?

[Victor]

I got a solid wood dining chair and the fabric seat is too stiff and rounded and 2 inches higher than I need.
Would fabric softener work? A seat cushion raises it higher. Foam rubber?
Or should I open the bottom and tinker with it?
Sure wish I could return it but cant

 

[Murrmurr]

Open it up and see what's inside. Maybe you'll want to replace the innards, or remove some of it. Or maybe the supporting structure of the seat cushion needs adjusting.

 

[Pepper]

Call a re-upholsterer. Shouldn't cost much. Worth it if you like chair.

 

[Knight]

Or you could see if any of the videos available would help you to decide.

recovering a chair - Google Search