* SIP ICE WATER. It keeps your cells hydrated and also helps you burn calories (by raising your metabolism, in response to the cold). Start the day with eight to 16 ounces of ice water. Sip a 16-ounce glass every hour or two, keeping one next to you at work and at home. All told, you should drink eight glasses a day. Finish up by 7 pm - to avoid having to get up to use the bathroom after you go to bed.
* BASK IN BRIGHT LIGHT. Most people get a powerful surge of energy from sunlight or bright indoor light. To make the best use of this effect, move your desk chair closer to a window, if possible. Or, better yet, take a five-minute outdoor walk every few hours. Indoors, replace incandescent or fluorescent bulbs with full-spectrum "daylight" bulbs from a lighting or health-food store (cost: $7 to $9 for bulbs, $12 to $20 for tubes).
* PERFORM MENTAL "CROSS-TRAINING." Cross-training is the process by which you "stretch" your mind in as many different directions as possible by engaging in a variety of mental and physical activities. Word puzzles and other games are an easy way to perform this cross-training. Other ideas: Pick a random sentence from the newspaper, then rearrange the words to make a new sentence, play Scrabble or do crossword puzzles, challenge a friend to chess or checkers.