I use an ex office table which allows me to adjust the height of the table and the adjustable chair allows me to set my thighs at the right height. As royjohn said, you need to listen to your body, time flys by when faceting and it is easy to lose track of how many hours you’ve had your ass planted on the chair so having both an adjustable table and chair allows you to establish the optimal position for your body.
Don’t make the table too small either, you need light/s, racks for your discs, a jug of water for topping up the reservoir, location for your diamond powder, and of course a mounting like a typists copy board for mounting your cutting diagram. Your table surface vanishes quickly and that’s without a location for your dopping station.
Good luck putting it all together.