Big meal

Treating myself to a big meal, of course, and opting to increase my position if there's any money left!
Increasing your effectiveness in doing things will increase your satisfaction and sense of achievement.
When you have completed a task, don't rush to start on the next thing just yet, but give yourself a reward. The confidence and motivation generated by the reward will in turn further enhance your effectiveness.
The reason most people can't start thinking creatively at the snap of a finger is that the brain is always tense like a spring and rarely relaxes, but it is precisely when it is relaxed that it is easy to settle down and think creatively.