Yesterday I made a new guitar seat to help anyone with a bad back from the footstool twist.
This is at present improvised from scrap wood.
Take a normal wooden chair .This will be better if you get rid of the back.A 3 legged chair would be even better.I started with a right angle joint made of two pieces of softwood 2inch square and about 11 inches long.Looking towards the front of the chair this will fit below the seat with two screws so the angle coming upwards leans at 60 degrees to the players left side.That will be (your) right if you are still looking from the front.
The section under the chair has to be shaped to fit flat against the underside of the seat.
( It`s easier to describe if I say it that way .Describing angled joints is a chore)
That leaves the last part to fit.The top of the 60 degree upright needs a small arm poking out away from the player with a 30 degree (horizontal) angle.That turns the "arm" to the player`s right which will match the side of the guitar which will rest on it.
This is also tilted upwards at 20 degrees (vertical) angle.
So,sitting on the chair, the wood will go up left and out and up right.
The section the guitar rests on will need to overhang an inch or two to the player`s right side to leave clearance for the wider bouts of the guitar.(where the upright section rises.)
Dont be shy about fixing a section of plastic rainwater guttering.(semi circular) to give a guitar friendly shape.
Once the surfaces that might contact the guitar are well padded with foam and covered with material you have a lovely relaxing guitar chair.
I also think it sounds better but that might be my imagination.
The guitar is lightly balanced by the player`s right arm and keeps a perfect neck angle .Some height adjustment will be necessary to suit different size players.I can reach out with both hands to move the music and the right arm still holds the guitar safely.
It only took an hour or two from scratch so you will enjoy making one.
All the corners and angles can be smoothed out and made presentable.
This little chair will have a great future.
To start off get in the best position for playing and get someone to sketch where the guitar curve is relative to the chair.This could be the start of a beautiful friendship if you play your cards right.