Exploratory testing is a great way to uncover information about the product you are working on
Part of exploratory testing is having charters to help guide the exploration.
On a previous project, I stored my charters at the bottom of the Jira stories. The reasoning was that a developer could pick that charter up with minimal effort if they were going to test a story. On another project, I was the only tester so a notebook was perfect for the job.
Where do you keep your charters and why?