Be aware. Be very aware. Staying hyper vigilant and aware of your surroundings in a parking lot is the best defense you can have. Scan your surroundings intensely. And, if your car has the technology, make use of it. Things like backup cameras and blind spot detectors come in handy when you need to see in all directions.
When it comes to that technology, though, you need to make sure it is well maintained and accurate. Things like hitting a pothole could throw cameras out of alignment. If there is a lot of salt on the road due to inclement weather, that can create a film of salt over camera lenses. Part of keeping aware means making sure your bells and whistles are in perfect working order. Keep cameras clean and make sure your computer is working right.