I have a normal desk with a cabinet on the sides and a hole in the middle for your legs. I found a super comfy recliner that when reclined, the part that holds your legs up fits perfectly in the spot for your legs under the desk. It also has a tray that extends out for the keyboard over my knees a bit, but I just put other shit on that tray, not the keyboard or mouse.
The recliner has two positions ...the first action ONLY extends my legs while keeping the back upright still...this is important, because some recliners tilt you back as the feet extend...you don't want that...you want the feet to extend first, and then have the second option of reclining your back if you choose. My recliner is not one with only a few set positions on the back rest, I can put it at any angle and it stays...you def want one that does these thing.
Because it has super thick cushiony arm rests, I put the keyboard on the right armrest supported by the arm and a perfect size pillow on my left leg. The mouse and mouse pad fit on the right armrest.
I put a 40 inch moniter on the desk in the center. Buying one that had the lowest stand-height from the surface of the desk (keeping it as low as possible). I also have a table to my left to put stuff on and also to put the keyboard, mouse, headphones, drinks, other fun thingys, etc on when I have to get up.
It is a bit of a pain getting in and out, but it is worth it the entire time I am playing.
I keep 40 lb dumbells on each side of my chair and try to use them for an hour each day on each arm, and I also do leg lifts and ab crunches constantly as I play, especially long 4-8 hour sessions.
I keep a second comp to my right on a sliding table for when I need it.
I use 60 ounce huge pitchers for ice water and unsweet iced tea.
ANd I get up every hour or two to pee/change the laundry/make food/ etc (all those stupid boring things that aren't gambling that I wish I could eliminate).
The most recent girl that lived with me called it my "spaceship" and she was really good about bringing me stuff so I don't have to get up as much. It is important to get a significant other that does those things too
Edit: Also, I move it every time company comes over and replace it with a normal computer chair. After a few wtf-looks from some friends, I found it easier to move it than explain to them its not a beat-off chair.