To swing arms in or out: While seated, grasp front end of armpad and pivot it to the left or right.
Adjusting arm angle can help support different types of work and shifts in posture.
Swing chair arms inward for support while using keyboard. Swing arm out to support use of computer mouse.
Increased tilt tension provides more stability and back support while you recline. Too much resistance may make it difficult to recline.
Depending on weight and preference, different people will require different levels of tilt resistance.
To increase tension: While seated, turn knob forward (clockwise, toward + sign).
To decrease tension: While seated, turn knob backward (counterclockwise, toward – sign).
Depending on the desired tilt resistance, a number of turns may be required.
To raise: While taking your weight off chair,
lift lever up.
To lower: While seated, lift lever up.
Instructions on this video show all possible adjustments. Specific adjustments vary according to chair model.
* Unique Pellicle Material
* Fully Adjustable Vinyl Arms
* Back Tension Adjustment
* Tilt Tension Adjustment
* Tilt Lock
* Forward Tilt
* POSTUREFIT LUMBAR SUPPORT SYSTEM
* Seat Height Adjustment
* Casters
Anyhow, the instruction is good (but I will never put it my play list).
Again, the sound is terrible but information is useful.
What happened with the sound in this video 
This is the funniest bit of guerilla marketing i have seen in ages -
Well Done Studio Boartdman