Bird droppings can cause bad damage to a car's paintwork so it's smart to try to get ahead of it. The best method is to invest in a decent car cover. Second to that, remove the bird droppings as soon as possible. They'll do much less damage to the paintwork if they don't sit on it for days at a time. Spray the droppings and wipe it off with a cloth, Meguiar's Quik Detailer (amzn.to/2S029MZ) is a good choice. Also, keep the car waxed. This will make cleaning bird droppings off easier. We generally recommend a polish like Poorboys White Diamond (amzn.to/2W4qYaA), followed by a sealant like Bilt Hamber Double Speed-Wax (amzn.to/2Wvdg59). Autoglym Rapid Aqua Wax Complete Kit is also a good option: amzn.to/2RS0rgA