As you already know, all materials wear in time. If the "new" look is not that important to you, add some wear to the fabric. take a look at a sofa in your house. You'll notice that the fabric of it is a bit worn out (less specular and maybe different in color) where people sat on it or leaned against it. moreover, Fabric is almost never without folds. Try adding some folds.
And, of course, you can always add some stains.