Do I need any brackets or hardware to mount this?

The cover is designed for DIY installation with basic hand tools. Specific mounting hardware details aren't confirmed — test-fit before committing to fasteners, and verify alignment at the bed rails.

Can I leave this folded up while driving, or does it need to be fully closed?

Tri-fold covers are designed to sit fully closed when the truck is in motion. Check your manual for wind load limits if you're carrying cargo with the panels partially folded.

Will this cover work with tonneau clamps or bed rail systems already on my truck?

Compatibility with aftermarket bed rail systems depends on your specific setup — measure the gap between your rails and the bed edge before ordering, since the cover mounts at standard Super Duty mounting points.