GhostsInside

Id like to run new outlets in my garage from an open 20 amp breaker I have. My question is in regards to NEC 334.30 b and c.

From the panel up into my attic, across the attic, then down a wall to where I want the receptacle. Am I required to open up the wall to staple it down? Or can I leave it unsupported as long as the drop from the attic to the receptacle is less than 4.5 feet and it's secured across the attic appropriately? Or will I be required to run it external in conduit secured to the walls?