There are many methodologies and concepts of how Design Thinking or Human Centered Design should be approached and there is no one right way of doing this. The activities and methods we use come from Luma Institute as we have had the privilege of advance training with them to understand their approach. They have a comprehensive approach to solving problems and we especially like their curated list of activities that will get the best results out of the participants in any workshop.
Source: Luma Institute
Here’s some other providers and approaches that are summarized in a chart:
Source : LinkedIn