Do you know what window films are? If your home is exposed to a lot of sunlight, they might be just what you need to cool it down. Window films come as permanent, semi-permanent and temporary films, and they can be installed fairly easily on your windows to keep the sunlight out. Most hardware stores will have window films for sale, sometimes in a range of styles and patterns.
If you decide to use a temporary or semi-permanent film, you have the advantage of being able to remove them when the weather gets colder to benefit from the sun’s heat.
You should be careful, however, when you remove it to make sure that you don’t damage the window. You should be able to get it off using a straight edge razor blade and some alcohol.
Installation is fairly easy. The film comes in rolls, and needs to be cut to size to fit your windows. Do not cut the film directly on the window since you can damage the window if you cut too deep.