There is strength in serenity. Deliberately exercising, consciously breathing in and out are possible ways of building brief periods of relaxation into your day.
If you're stressed and tense, active recreation (hobbies, sport, nature etc.) is more effective than passive relaxation.

What's your situation?

• What activities are most effective in helping you to «switch off»?
• Does your daily schedule include regular slots for unwinding?
• What activities – writing, running, handicrafts – give you strength and momentum?

A few suggestions:

• Make time for breathing and relaxation exercises – first thing in the morning, perhaps.
• Try out a relaxation technique – autogenic training, yoga, qigong – and build it into your schedule. Plan a boat ride at the weekend, a trip to the mountains, an afternoon's reading on a lounger or the sofa.