When approaching the car always have your keys in your hand, key blade unfolded (open) if it is a folding key.
Always scan the area, know what is around you and keep an eye out for trouble, anyone hanging around. Check for shadows. Use your surroundings i.e. reflections in your car’s body work, the windows – if some is approaching you (even if from behind) you will see their reflection.
Get in the car, lock the doors and start the engine – only then should you put your seat belt on – and go.
When parking, always reverse into the bay so that if you had to drive off in a hurry you could do so. Better visibility driving straight out forwards, having to reverse out would take more time and you would need to exercise greater caution (possibly giving someone the chance to apprehend you).