I used a mesh material that I bought, oh, a year ago. I trimmed it with satin blanket binding, and made ties from bias tape. It's one piece that kind of weaves in and out of the crib bars (at the corners) and joins with velcro.
I used lavender, so that it will go with the quilt that my mum made and sent over for Lainey. Isn't it lovely? I love Beatrix Potter!