The arms on this chair have obviously seen better days. Although the foam was not breaking down and could have been reused, my client decided she wanted it to be replaced. Replacing foam on furniture is quite costly, but it is sometimes necessary. If a chair smells bad, either from cigarette smoke or lingering pet odours, it is usually the foam that is the culprit. I find it can act as a sponge for bad smells.
Then I tacked it in place. I made my pleats on the front of the arm by securing the fabric at the bottom of the arm first, then pulling it up firmly. The pleats should be spaced evenly, and identical on both arms!
The finished arm is round and full. And of course, I made arm caps (click here for DIY) to protect them!