The Busy Person’s Guide to Reducing Stress : zenhabits
1. Be completely in one task.
2. See your ideals, & let go of control.
3. Accept people & smile.
4. Take a brief walk.
5. Do short mindfulness practices.
And beyond: If you have extra time after doing those things, I have a few other recommendations that will help. Eliminate unnecessary tasks on your todo list, reduce your commitments by saying no to people, start a regular 5-minute meditation practice, eat healthier, exercise regularly, spend some quality time with loved ones, get more sleep, drink tea.