Tenax Garden Netting - Black Plastic Hardware Netting - 3' x 15' - Plastic

I leash/harness trained my cat and zip tied something like this to the railing. Took us a few months to get the hang of it but now we can easily spend two hours outside (i bring a water bowl and a snack for my cat for that long). She is always on a leash, the leash is always in my hand, and I watch both her and our surroundings to make sure she stays comfortable. r/adventurecats and r/cattraining might be worth a look.