Make a 2x5 of wood planks
Add a hole in the back middle
Place a redstone torch in the hole
Then cover it up and place a iron trap door
Then make another hole in front of the first.
Add an armor stand
Then add a chain mail helmet on top of the armor stand.
Add a piston two blocks on top and the wood you used under it.
Activate the piston.
Then mine the piston and add a picture on the trap door.
On the right hand side of the computer put a stone button.
Thank you for looking at this guide everyone. Also if you want a chair to go with it make shur to check out my other guides. See you later