1. Spend 5 -10 minutes almost every day in doing manual calculations.
2. Avoid lifts and take stairs whenever possible.
3. Write at least one page every day. Writing helps in maintaining coordination of hand fingers and brain.
4. Staying actively involved in doing real business dealings helps you to comprehend multiple real-life things simultaneously, this helps you remain mentally active.
5. Remain socially active and explore opportunities on how you can help others. It keeps you think from others point of view this helps in maintaing your relationships.