I haven`t worked on these specifically, but they look like alcantara from the pictures. If that`s the case here are my processes.
I use a specific upholstery cleaner called fabric master HD, it cleans the things commonly found here: grease, body oil, dirt and self neutralizes. I spray a towel and gently wipe to avoid messing up the fibers. For any pilling I use 2000 grit sandpaper, again, gently. For any matted areas I use the leather master nubuck cloths. For any difficult grease stains, like mechanics grease, I use everclear (this is the only time I advocate 90% grain alcohol in the driver seat).
Avoid soaking the fabric and overworking it if possible.
As a side note, fabric master HD also works wonders on contrasting stitching on leather seats and steering wheels.