If you are a person who easily forgets things, make a mental checklist before leaving your home. Ask yourself what you usually bring with you and check to make sure that you have it. By doing this, you are reducing the risk of going somewhere without something you may really need.
Sleep is vital to maintaining mental clarity and memory. By avoiding sleep, you make your senses and mind foggier, hurting your ability to focus and piece together information. In addition, during sleep, your brain forges pathways that lead to memory. Getting good sleep (and a good amount of it) will improve your memory.