ALWAYS lock your windows and doors when you are away from your residence. Even if you are just stepping out for a quick errand. Most burglars are in and out of a house in less than 3 minutes.
Do not leave spare keys hidden on your property. Most thieves know all the common spots in which they are hidden.
Make sure the exterior doors are solid core wood or metal.
All exterior doors should be equipped with dead bolt locks that have a minimum bolt throw of 1 inch.
Remove the screws in your strike plates and install others that are at least three inches long.
If you have a sliding glass door wall use a wooden dowel as a means of bolstering the door lock. Lay the dowel in the track near the bottom of the sliding section. This will prohibit sliding the door open in the event the door lock is compromised.
On door walls, "back-off" the screws in the upper track about 1/8 to1/5 of an inch. This will not interfere with the operation of the door, but will prevent the door from being lifted out of the frame.
Drill a hole through the frame and the door glass frame. Install a bolt that fits to prevent the door from being lifted out. These kits can be purchased for a low price at most hardware stores. They are easily installed.
Attach similar pins in windows all over your house. This will prevent criminals from forcing window locks. An entire house can be equipped without great cost.
Install a peep hole viewer in all your doors. Make sure it has wide angle viewing of 180 degrees.
Use timers on lights and be sure to stagger the pattern of lighting. Light different rooms at different times. Be creative. Get out of the habit of leaving the living room light on, night after night.
Leaving the TV on in a dark room is an excellent idea. Leave the volume up too. The motion of the lighting will throw thieves off. It is no less safe than using table lamps, and just as cost effective.
Install exterior lighting. Make sure it is evenly distributed and does not create deep shadows. Poor lighting can be worse than no lighting. Landscaping lights are functional, as well as decorative, if properly spaced and directed.
Make sure that no bushes or trees obscure windows or doors. Over grown landscaping can provide excellent coverage. If you have basement windows, install glass block windows. They are an excellent, attractive means of securing lower lever windows. Prune bushes at least 18 inches from the ground up.
Many burglaries occur through second story windows or patios. Make sure that any trellises or trees do not provide access to upper levels.
Engrave and list all your valuables. Photos are a good idea to keep inventory of property. Video is even better