Help with upholstry - for hard backed chairs

[Katymac]

OK I might buy some chairs for the nursery (recycled so very 'green')

But how do I (or even can I?) pad the seats and finish them off neatly?

The seat and the back are screwed on from the front - so where I would normally recover them and screw them off, cover them, then screw them on from the back I can't because they aren't thick enough

Any idea or help?

That's an idea

Still leaves the problem of what material to use - wood is so difficult