Recommended equipment - balance cushion (blue cushion in the photo)
Although you can use couch cushions, it really depends on the thickness of the cushion and size of your dog.
If you're wanting to buy a cushion then I suggest one of these.
The foam is strong so your dog's nails won't destroy it but it is soft enough to challenge their balance and proprioception.
This is the one I use.
https://amzn.to/483mlEw
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