Relief cuts, slow and steady speed. You'll want to stop/ start as little as possible and keep the work you're feeding flat.

Finished this up last week. The seat and kicks were built in house, the door panels were from Rod Doors and provided by the customer to be covered to match.

I just finished a set of Recaros similar to those. Something else I ran into was my regular stapler couldn't get deep enough without leaving exposed staples. Grabbed a new long neck that did the job. I spent 3 different attempts perfecting those dang things but finally got something to be proud of.