The height of the chair depends on the length of your lower leg. Women should allow for the height of the heel of the shoe you are wearing. You must feel no pressure on the back of your thighs.
If you like to sit in a high position, it is important to move forward on the seat and leave the seat tilting loose. Use lever in the left side under the chair.
The lower back support should support the lumbar below the loin to give the lower part of your back the best support.
The upper back support should be placed below the lower points of your shoulder-blades to give the upper part of your back the best support.
The two back supports may be raised in small steps. Hold with both hands under the back support and pull upwards in small jerks. If the back support comes up too high, pull it all the way to the top/starting position.
The chair should move easily backwards without giving you the feeling that you tilter backwards. To adjust tension turn the knob under the seat.