Here is a memory tip that I heard about this last spring and I decided to test it all summer... After trying this many times, I can confidently report that IT WORKS!
If you ever wonder after you leave your house whether you locked the front door, turned off the AC, put on the outside lights, etc., learn to say it OUT LOUD AS YOU COMPLETE THE TASK. Example: "I am locking the door now." "I am turning off the AC now."
We all know when we are rushing to get out the door how we perform these menial tasks out of habit, but later you begin to doubt yourself. Did I lock the door? UhOh, did I turn off the iron? Is there food in the cat's dish? The answer is to use this tip. In no time, you will stop asking yourself if you locked the front door because you will clearly remember saying it out loud as you did it!
This memory exercise works because stating the task out loud cements the act in your memory. It seems silly but when you are on the airplane, sitting on the beach, or driving to work, you will no longer have to fret about whether you did the task or not. Ahhh, easy enough and worth a try!