1. Read often
Set time aside to read each day. However, don't always read the same type of books. For example, if you are a fan of mysteries, mix it up with a historical biography or science fiction. Subscribe to several newspapers - your local paper, the Wall Street Journal and a trade publication that interests you. Try to read the paper each day before leaving for work.
2. Do puzzles
Crossword puzzles, Sudoku and other word puzzles are terrific ways to work your brain. What's great about puzzles is that they are available online. In days gone by, you could only find crossword puzzles in newspapers or magazines. However, you can now choose from thousands of puzzles on the Internet.
3. Use your opposite hand
If you are right handed, try to use your left hand to do everyday tasks (and visa-versa). By switching hands, you will be exercising the opposite side of the brain. Some tasks will be extremely difficult at first, but over time you can train yourself to be ambidextrous in many instances.
4. Play video and online games
Despite what you might read, not all video games will turn your brain to mush. In fact, many games are designed to improve your memory, develop logic, increase mental speed and boost creativity. Look for "brain games" such as chess, memory games, logic puzzles, word games and many others.
5. Learn a foreign language
One of the most powerful ways to exercise your mind is through learning a new language. Take a course at your local community college or language school. If that's not convenient, you can learn a foreign language online or by listening to tapes.
There are many other ways to exercise your brain such as practicing meditation, doing math problems, learning to play a musical instrument and expanding your vocabulary. The key is to avoid getting into a routine. By changing your day to day activities and taking on new challenges, you can improve your mental capacity and stimulate your brain.