Read. Read as much as you can. The more you expose yourself to new words and new ideas, the more your brain has to expand to take it all in. Look up words you don't recognize to improve your vocabulary. You can read the newspaper, books, journals, websites, you name it. Try to broaden your horizons and read about new topics. You will not only learn more about a variety of subjects, but you will also be a better conversationalist at your next dinner party, able to discuss politics, recent events, movies, culture and more.
Try something new. Whether it's learning a new language, a new dance step or a new route to work, giving your brain a challenge can improve your smarts. The UCLA Center on Aging has shown that mental challenges bolster connections between brain cells, allowing them to better communicate.
Likewise, a study from the Rush Alzheimer's Disease Center in Chicago revealed that elderly men and women who continued to challenge their brains lowered their risk of getting Alzheimer's disease over the next four years by 33 percent.
Exercise regularly. In a study of young people (ages 18 to 27) at Rhode Island College, researchers proved that 30 minutes of aerobic exercise boosted creativity as well as the amount of oxygen to the brain, which boosts memory as well.
Meditate. Studies have shown that a daily meditation practice---simply sitting still and noticing the breath as it comes in and out through the nose---can thicken the cerebral cortex, the part of the brain responsible for memory, attention and decision making. In addition, meditation can also calm the mind and nervous system, leaving you more alert and relaxed, capable of absorbing new information and handling stress.
Memorize. Whether you memorize a poem each week or even a few lines from your favorite book, memorization stimulates neural pathways in the brain, reducing memory loss and other issues related to aging.