Your three basic window covering options for blocking light from outdoors are curtains or drapes, mini blinds, and shutters. They all are effective and will also provide more privacy. Shutters, particularly louvered ones, are not quite as effective for privacy as the other two because there will still be small gaps that someone may be able to look through.
Take an inventory of your windows of concern to determine which could use miniblinds or shutters. Installing either is not a difficult do-it-yourself project, but installing the shutters takes more time and attention to detail. If installed properly, however, shutters are certainly more attractive than mini blinds.
In general, mini blinds are effective on south- and southwest-facing windows. These windows get the most exposure from the sun in both summer and winter. Mini blinds provide precise control over how much sun gets through but allow you to close them completely for privacy. During winter, you may actually want the sun to shine in to help heat your home.
For windows where you want shutters, custom-made ones are the easiest to install, but also the most expensive. They can be sized to the exact dimensions of your windows, and they are delivered with all the matching installation hardware and hinges. Most of them will also be finished, so all you have to do is attach them.
If you cannot afford custom shutters, buying unfinished louvered shutters at a lumberyard or home center store is the least expensive option. Expect to have to do a substantial amount of hand sanding. When finished nicely, however, they can look very good. They range in size up to about one foot wide and four feet long and should cost between $25 and $50.
Louvered shutters are typically installed over only the lower half of the window for privacy. In your situation, where you are attempting to also block light from a floodlight, buy ones tall enough to cover the entire window. For windows where the floodlights are not an issue, size them to cover just the lower half. If you have double-hung windows, align them with the top edge of the lower sash.
The first step to installing the shutters is to make sure the window opening is square. If it is not, you will have to trim the shutters slightly. Use a power saw to get a clean cut. Taper the sides on each panel (there are two panels per side) so the difference in width is not as apparent.
With the shutters cut to size, connect each set together with non-mortising hinges for simplicity. Eight hinges are usually used for each window. Shutter packaging often includes detailed instructions for its specific hinge design.
