I have converted one of these
food boxes from IKEA that I had lying around as the sand pit. I kind of have it half buried in the substrate with a bendy to help get in/out (not that she ever uses it as a ladder). But what I have noticed is that it doesn't really seem to help much since Gaby always likes to walk out of the sand bath completely covered in sand and shakes it off quite far away from the bath! So the other day when I had to move her cage and emptied out all the substrate, I found a layer of sand all over the bottom of the cage. Lol