Exposing yourself to sunlight in the early morning actually triggers a cascade of psychological reactions that boost your focus and productivity levels. A short stroll has the added benefits of movement and fresh air, but drinking your tea outdoors or sitting by the open window for a few minutes also helps. I also love lists; both to unburden my mind - less to remember! - and to plan my day, energy-wise. If possible, I do high-focus tasks during the time of day when my concentration is highest and save low-focus tasks for not-so optimal periods.