Identify the first letter of each general category of the Dewey Decimal Classification system to simplify the memory task. Use "C" for computer science and general publications (000-099), "P" for psychology and philosophy (100-199), "R" for religion, "S" for social sciences, "L" for language, "S" for science, "T" for technology, "A" for arts and recreation, "L" for literature and "H" for the history and geography classification.
Arrange these letters (CPRSLSTALH) into a mnemonic, or memory device. If you prefer sentences and rhyme, you might like this example: CPR Saves Lives; Stings, Terrible Allergies Lead (to) Hives. Alternatively, visualize your favorite meal: Chicago Pizza, Red Sauce, Luscious, Sumptuous Toppings, Anchovies -- Like Heaven! Use personal visualization techniques, oral rhyming cues and meaningful clusters to stimulate your memory.
Practice association games to strengthen your memory. At an elementary level, the Pacheco Union School District offers a simple flashcard game to associate the general classification with its number range. Quintessential Instructional Archive offers a matching game; when you click on the correct category and numerical reference, the identical images indicate the correct answer. Popular web sources also feature Dewey Decimal rap songs.
Reinforce your associations with trips to the library. If you need a travel guide to a destination, search your memory for the numbers related to geography: 900-999. If you need a play by Shakespeare, you will assume it is somewhere in the 800-899 area. To compare religions, seek the 200-299 area instead of simply searching within the library's database. As you locate your information, you will strengthen your memory and find other resources you never anticipated.
Note exact decimals for frequently used areas of knowledge. For example, if you love Shakespeare, you may commit to memory his special place within the system. His number -- 822.33 -- distinguishes him as the only author to have his own Dewey decimal number. Locate the exact numbers related to your special interests.