My hand fed to adulthood cat Nilla needed a new home. A cup box from work has become the perfect place.
Step 1: The Materials
Not very much
1. A heat gun
2. Hot glue
3. A cardboard box
4. Eva Foam
5. Any sharp knife or scissor.
Step 2: Mark Holes
Use a good marker.
Make the holes about 3 to 6 inches. The cat has no collar bone but still needs space to manuver it's limbs.
Step 3: Cut Holes in Box
I recommend an exacto knife. If none is available, use a razor or a box cutter. Be sure to make it 3 to 6 inches.
Step 4: Bend the EVA Foam and Put It Inside.
Use your heat gun to bend the EVA Foam to a shape like this
Then glue it to the walls inside
Step 5: Cut Off the Top
Cut off the flaps to make it open. Cats prefer it to be open.
And now your Cat house is complete. I use a treat or cat nip to lure them in. Don't force them however, let them go in on their own time.