Below are some tips to help prevent becoming a victim of theft or burglary.
Keep all windows and doors closed and locked when you are not home.
Consider using an alarm system which is monitored and can provide police with timely notification of a possible burglary in progress.
Keep valuables out of sight, including the packaging of valuables which may be in your trash or recycling.
In the hours of darkness, use moderately bright and even light (white) to illuminate your home and the area immediately surrounding it.
Consider employing bright motion sensor controlled lights (white) for avenues of approach to your home.
Keep your landscaping neat and trimmed, with shrubs trimmed low to allow visibility over them, and tree canopies trimmed high to allow visibility under them.
Keep record of the make, model, serial number, value, and a brief description of your valuables (this can be very helpful for police in follow-up investigations and essential in recovering your property).
Consider locking your side yard gates.
Consider planting bushes (preferably thorny such as roses or bougainvillea) under first floor windows.
Keep all windows and doors locked when you are not in the vehicle.
Never leave the vehicle unlocked and running to warm up (consider a remote start system).
Do not keep valuables in your vehicle, and if you do have to keep things in your vehicle, make sure they're out of sight.
Consider the use of an alarm (do not mistake a "security system" for an alarm).
Park in a well-traveled, highly visible place with good lighting.
If you are going somewhere and need to leave your purse / wallet in your vehicle, place it in the trunk before you leave, not when you get to your destination (do not try to hide it under the seat when you get there).
Do not program your home address into your GPS unit (program a major intersection which you are familiar with if need be).
Black out your home address on your vehicle registration, photocopy it, and keep the copy in your vehicle.
Keep your glove box and center console locked if possible.
If using a valet service, provide them with a valet key if you have one (typically grey in color and provides limited access to your vehicle).
When on vacation
Keep all windows and doors closed and locked while you are gone (and alarm set if you have one).
Have a trusted neighbor or friend keep an eye on your house (preferably with a key to access it in an emergency)..
Ask the postal service / newspaper service to hold service during the time you are on vacation.
Have inside lights and a radio on a timer to give the illusion that you are home.