1) Design thinking is an iterative process used to address 'wicked problems' by seeking to understand the user, challenging assumptions, and redefining problems to identify alternative solutions.
2) It involves 6 steps - empathizing with users to understand their problems, defining the problem from their perspective, ideating many solutions, prototyping ideas, testing prototypes with users, and implementing the best solution.
3) The document provides an example of how design thinking could be applied to address the challenge of increasing sales of an insurance product bundled with home loans at two banks, which currently has only achieved sales of 100 crores against total home loans of 750 crores.