use a good chair with a dynamic chair back and sit back in this
top of monitor casing 2-3″ (5-8 cm) above eye level
no glare on screen, use an optical glass anti-glare filter where needed
sit at arms length from monitor
feet on floor or stable footrest
use a document holder, preferably in-line with the computer screen
wrists flat and straight in relation to forearms to use keyboard/mouse/input device
arms and elbows relaxed close to body
center monitor and keyboard in front of you
use a negative tilt keyboard tray with an upper mouse platform or downward tiltable platform adjacent to keyboard
use a stable work surface and stable (no bounce) keyboard tray
take frequent short breaks (microbreaks)