Write an article based on this summary:

Trim the flaps off a cardboard box with scissors or a utility knife. Measure and trim the box if needed to fit it in a cage. Leave the glue for 24 hours to dry if you used any.
Unfold the cardboard box and lay it flat. Peel off any tape holding the flaps in place. Then, remove the flaps so your hamster has plenty of space to move through the container. Make the toy out of plain cardboard. Avoid using tissue boxes or other types of cardboard with ink, since ink can be harmful to your hamster if it is chewed and swallowed. If you make the toy out of a big cardboard box, cut it to size with scissors or a utility knife. Choose a good spot for the toy, then use a tape measure to determine how much space you have available. Mark these measurements on the cardboard before cutting it.  To reduce the amount of measuring and cutting you need to do, use smaller boxes like tissue boxes. Save bigger boxes for toys left out of a cage, such as those placed inside a playpen. Another way to make use of a bigger box is to cut it into panels. Trim the panels so they’re all the same size, then stack them and glue them together to create a box-shaped house. The glue will begin curing within a couple of hours. Wait for it to completely solidify so the decorations don’t fall off when your hamster starts climbing on its new toy. Waiting is important, especially if you used a hot glue gun.