TLDR; Prioritise, timebox, constrain, distribute, automate, document, and be flexible about your research activities.
In which I'm still focusing on The Market and staying abreast of the Changing World (and basically thinking out loud about the model of product management I'm working with and how to accomplish my goals as a PM).
How do you learn about the world or the marketplace in which your product and business are operating? How do you analyse the marketplace, and turn the results of your analysis into actionable insights?
I found a model I liked and repurposed it for representing what product management could/should/might look like. You can apply the model by continually asking the question 'What's really going on here?'