2. Think before reacting
We are always facing different situations in life. Mostly we react automatically to these situations. If it is something that may lead to a change our immediate reaction is resistance, a no.
3. Go for walks or be in stillness
Personally I recognize that walking is something that stimulates my mind and my thinking. To be outside gives fresh air and gives a chance to experience nature or whatever is in the surrounding. It increases the intake of oxygen and makes the brain more alert and clear.
4. Solving crosswords, playing chess and similar things
This is things we do where we have to use your brain to figure out solutions. Solving crosswords is one example, playing chess another.
5. Colors stimulate
Colors is also something that stimulates the mind. If you want to get attention from the mind you can use strong colors. We can see this in advertising on the Internet where the advertisers emphasizes the most important words by using strong colors.