Pretty simple fella, take them out than just look at them for a bit and its self explanatory. Look at the rear of the seat and you will see two zips, the lever for the seat tilt is two allan key bolts and then this comes off. Pop the plastic switch knobs off these are easy to do. Then you have philips screws holding on the side trim.
Now remove the plastics off the opposite side, once thats done unzip the rear cover iirc the bottom is clipped over a bar. You can now start removing covers. For the base cover its also clipped on iirc. Off the top of my head the head rests are removed by releasing the clips inside the back of the seat.
Hope this helps you.