Here is one idea that is not talked about a lot, but will not only help you creatively but also physically.
Listen to your body
It's so easy to override the messages our body send us, like when we are hungry, when we need a break from the computer screen, or need to get some fresh air, but what if we listened to those messages and took the necessary breaks to be more relaxed.
Our body knows best. Listening to its cues will guide us to having a more relaxed mind, therefore being more creative.
Do you listen to your body for cues to take breaks?