Your ideas need space to work themselves out - John Seely Brown said, "For imagination to flourish there must be opportunity"- and that opportunity is space and time.
Give yourself the problem to solve. Analyze it. Ask Why, How, and What If questions.
Take yourself out for a walk. Think about those questions while walking. Play with the idea the way a cat plays with their food.
Re-approach the problem later in the day and see if you're problem solving has improved.
I make an effort to take walks in the middle of the day - when the day is brightest. Perhaps giving myself time to think is the "brightest" part of the day. Pun intended.