Many times the easiest way to cool a garage is to open the garage door. But doing so means that anyone passing by can see inside your garage and take notice of what valuables you own.
Adding garage vents accomplishes the same thing as opening your garage door, but without exposing everything to the public. The vents can be installed in the glass panels of your existing garage door or in the walls of your garage.
The following photos show some options that are available to you: