This is probably the most common technique used in memory improvement courses, and it's called Visualisation. This is where you take a list of items that you want to remember and associate it with images in a story-like fashion.
For example, say you need to remember a list of items to take for a family day at the beach. To help you remember the list of items you associate each item on the list with an item that you are familiar with on the walk from your bedroom to the front door.
i.e. The first item on your list is the umbrella, imagine yourself in your bedroom just about to walk out to the door, but you can't get through the door because there is a big umbrella that is open and it's blocking the doorway. The next item on the list is sunscreen, imagine that it's smeared all over the door handle, making it slippery and gooey. Next you pass the hall lamp and it's got sausages sticking out the top of. Try and make the images as ridiculous and vivid as possible to make them stand out in your brain.
You keep doing this through the whole list of items, associating each one with an item on your path from the bedroom to the front door.
With practice, this process does become easier and quicker, but you will need to stick at it for a few weeks to get it ingrained into your mind and become a habit.
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