Realize those standard memorization techniques that most people learn as children allow them to only remember seven or eight things, but not much more than ten. Phone numbers, social security numbers and even grocery lists are good examples of things easily memorized because they are limited. Longer lists of 20, 30 and even 50 items require a new technique.
Open up the imagination door of the mind. This is easier for naturally creative people, but everyone has an imagination, it may just take a little practice to get it in shape.
Make a mental picture of your house, or some place that is very familiar to you with lots of different rooms.
Pick a room that is either the first room you enter when you walk into the house or building, or start with how you go about your day, beginning with waking up in the bedroom. Whatever room you choose to start with, it should follow either a logical order of moving through the building.
Look at the list and picture the first item in the first room chosen. Don't imagine it on a dresser, but pick something so absurd that it makes you laugh out loud or smile to yourself. The more outrageous it is the better. Develop a good mental image before moving onto the next item.
Move down the list in sequential order, and through the building in order, developing images of the items in different rooms, using as much imagination as possible. Spend a few seconds at least on each item, really visualizing the items to help you memorize them.
Picture two or three items together in each room when working on memorizing really long lists in order. Outrageous is key, but when lumping things together, they should fit in a natural way or somehow be linked together. An old car is in the bathroom with a hairy dog driving it while using a blow-dryer is one way to link car, dog, hair-dryer.