Popsugar Living Cars Car Hacks 19 Insanely Cool Car Hacks You Should Try Out 22 June 2018 by Tara Block View On One Page Photo 13 of 19 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 13 Use the tennis ball trick to avoid banging your car against the garage wall. Hang a tennis ball from the ceiling so you'll know exactly when to stop backing up. Previous Next Start Slideshow CarsHome LifeLife HacksDIY