
I assume you have puppy panels, If you have a large piece of lino cut off, or heavy duty plastic/tarp you can do what I do and use 4 panels one with a gate to make the side and put one across the top for rigidity.
This will enable you to drape a blanket over the top to make a den.
I then tie cardboard all the way around up the sides, at least 12 inches high.
I use a heat pad, shredded paper and vetbed.