are we calling it Brown, Karen ? Hybrid ? Rainbow ?
for the effort of having a muslin pattern made ahead of time ( which serves at estimate time for a closer number and allows the half deposit to be demanded at that time anyway.....)
you can have a glue basted ( think many fewer pins and no time hunting for a way to insert them while avoiding the chair ) RS out fully fitted cover, lined and even stuffed ala the Maureen Whitmore craze ( but we can skip that too ).
Measurements can be substituted for the muslin in some cases, but a good premade muslin pattern serves so many good uses, and many people make them already.
General idea : the outside body pieces are steamed, cut to size, corded and lined. They look pillow cased when done, they are separate, not joined to anything. They are overlocked at the skirt line, and are longer than needed.
The inside body pieces are steamed, lined, assembled to other inside body pieces. They are cut to size but left long to underlap the outside body pieces.
The outside body pieces are prepared with Rowley's fuseable web, 2" on the lining side, and pressed with release silicone paper. Outside body pieces are ready to fuse when positioned.
Inside body pieces are positioned ( already joined, lined, overlocked ) pinned into the chair so as to make as tight as desired and overlapped into what would be the areas covered by outside body pieces....O back, arm front panels, O arm, De fronts, DE side panels, O wings if any, O side panels if any.
The outside body pieces are applied positioned, tightened, pinned, and fused. Skirt line cord is fused at this time as well, ready to receive the skirt once stitched.
Stittching is done from the front.
Lining used can be cheap and removed ( with the fuseable ) as soon as no longer needed, or kept as part of finished product.
Weird, no ? Fun for me, I like fun. Wicked fun, I have been waiting to glue a slipcover all my life.....