Filling it with rolls of paper towels (5 doubles for 16” diameter) and tucking a few  bags of brown sugar or rice between them at the bottom produced a basic shape that stood up by itself in  three days. After a week of using it for laundry, it looked fine. A little bigger than I thought but a full bedding change plus a light blanket fills it. The blue is more dark teal than navy but very attractive. The whole basket, including the “built-in” handles, seems to be quite sturdy.
I like this one so much I’m getting 2 more!