Photographers often seek out the “golden hour”, the period of time shortly after sunrise or before sunset, where the light from the sun is warmer and softer than when the sun is high in the sky. Just as there is an optimal time of day to take photos, we all have periods of time throughout the day where we are at our most productive. Some people find that they can focus better in the early mornings, or late at night. Others do best in the middle of the afternoon. Think about when you might be at your creative best, and try to find a way to work during that time.
If you can’t shift your schedule around, it may be good to think about other lifestyle changes that will increase your productivity. For example, a burger at lunch may not be a good idea if you have a lot to get done after lunch, as your body will pool resources into the digestive system, which will certainly make it more difficult to stay focused and productive.