By switching from one kind of task to another you give your creativity just the boost it needs. Take time off. We get in the mind set of feeling if we aren't working every possible minute of every day we won't reach our potential. That is probably true for a computer, but you aren't a machine. Your body, made of water, carbon, and chemicals, was never designed to run like a computer.
Some cultures only work every other day.
Others take frequent holidays. Yet, somehow, their productivity is high enough to give them a successful and satisfying life. Improve your surroundings. We spend a lot of time making sure our computer has the right motherboard and RAM running at top speed. We should be just as concerned with putting a plant near our desk, getting an inspiring painting for the wall, having a view to the outside, and a comfortable chair.