Measure Your Windows
When making your own homemade security shutters, first measure your window for the dimensions of your shutters. For the height measure from a half inch from the bottom to a half inch from the top of the window, as you will want the shutters to fill the entire space of the window frame, but not drag against it. For the width, measure the entire window frame crossways from one side to the other and then divide that in half, as each shutter in a set will only cover half the window.
Buy the Right Wood
Pick out what type of wood you want to use to make your shutters. Standard shutters are made out plywood, but if you want stronger security shutters, redwood or pine might be a better option. These pieces of wood will be more expensive and slightly more difficult to cut and construct but will also last longer. Also keep in mind how heavy the shutters will be once they are constructed out of this wood. Your hinges will have to be able to hold them off the window sill and prevent them from sagging as they swing open.
Buy the Right Hinges
Buy heavy-duty hinges that can each hold an ample amount of weight, even more than what your shutters themselves weigh. Also measure your window frame, to ensure the shutters can be screwed into the window frame itself. While you can install the hinges on the outside of the house, someone trying to break in could unscrew the hinges and remove the shutters to climb in the window. So if you do decide to install the hinges on the outside of the house---or must because your sill is too narrow---make sure you strip the screws once they are installed, so it is difficult to remove the hinges without the proper equipment. You want to buy four hinges per shutter set.
You can add many different types of locks and latches to the inside of your window shutters once they are installed to lock them into place. A barrel bolt lock is one of the cheapest and most efficient locks; these barrel bolts are simple sliding bolts often used on the doors of bathrooms and other areas in some houses. Simply screw the barrel bolt into one shutter and the metal plate it fits into to the other side. These should be installed while the shutters are closed so that the two parts are directly aligned with each other and they can lock efficiently.