I work to keep my energy level up and my mind focused. For me this means getting plenty of sleep, eating well, regular excercise, and time for relaxation. (And often, classical music at work).
I try to increase my focus by creating large chunks of time dedicated to programming. This means turning off my e-mail, setting the phone to "do not disturb". I also like to turn off the lights in my work area and rely on the sunlight coming in through the large display window next to my desk. It's a nicer quality of light, more relaxing.
My break through ideas often come as I stand up and walk around or a take a juggling break. My walks to work are also a good source of ideas.
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