The Greek philosopher Plato described memory as a "bed of modeling wax" that holds on to impressions as if they'd been imprinted by a signet. How to improve your memory has proven to be only slightly more complicated than Plato's modeling wax. Here are some tips from experts:

*Adapting the Roman loci technique to our times, select in your mind a familiar place, such as a mental image of your own home. Envision yourself walking systematically through it, identifying landmarks -- the front door, the living-room couch, the table in the kitchen, and so on. Identify each item you want to recall with one of the associative points. To memorize ancient Roman emperors, for example, envision Caesar Augustus welcoming you at the door, Julius Caesar sitting on the couch, and so on, before Hadrian lets you out the back door.

*Forming mental pictures with the information to be remembered helps preserve a memory, says mnemonic expert Robert Montgomery, who uses the acronym ACE -- for Action, Color and Exaggeration -- for his imagery method. Montgomery says it's effective to "stack and link" images, and the more ludicrous the better. To remember the 13 original colonies, he says he envisions, " . . . a delicate china plate; jammed into it is a huge fountain pen cracking the plate . . . on top is King George in his royal robes; a bandaid is connecting a cut on King George's face; and so on." The colonies memorized? Delaware, Pennsylvania, Georgia, Connecticut . . .

*Make up your own verbal structures, cadences and rhymes, such as "Spring ahead, fall back" when setting clocks for daylight savings time, or "30 days hath September . . ." to recall the days in the months.

*Invent acronyms, recommends memory trainer Harry Lorayne. The word HOMES, for instance, contains the first letters of the names of each of the five Great Lakes.