I'm going to do something similar to MackTheHunter's ChairDesk.
Step 1: Acquire computer chair, plank of wood, bending aluminum tube, nails, and a few tools
Step 2: Put bending aluminum tube under cushion area and attach to wood
Step 3: Put keyboard and tablet and mouse on said plank of wood
Step 4: Make a hole in the armrest and put a net so it can be a cupholder
Step 5: ???
Step 6: ChairDesk with tablet and cupholder
one flaw, the tablet is wired.