One way to break out of a mental set and expand thinking is to approach problems from different perspectives. This can involve challenging assumptions, brainstorming new ideas, and seeking out alternative solutions. Another method is to take a break from the problem and come back to it with fresh eyes. This can help individuals to see the problem in a new light and generate new ideas. Practicing mindfulness can also help individuals to become more aware of their mental sets and be more open to alternative perspectives.