I am not a fan of washing your car at home in the driveway. There are voluminous studies of just how bad this is for the environment and city run off. But I do accept that folks are going to wash at home no matter what.
So, if you are one of those folks that insist on washing your car at home, at least check out this post from Consumer reports listing some good info about how to do it right. For instance, you don’t want to use dish soap on your car as it can strip the wax off!