You can use a number of tools to support, automate, and visualize the process. Jira and Agilefant are well-known web-based solutions that can help you define epics, stories, estimates, and sprints. Most tools also have an option to add (sub) tasks to stories. Although a story should be the smallest amount of work possible, it can still be useful to divide them into multiple subtasks.
You can find more information about Jira at https://www.atlassian.com/software/jira. Agilefant can be found at https://www.agilefant.com.
The following is an example of Jira displaying a Kanban Board. Jira comes with good support for Agile and Scrum in particular, while Agilefant is more method agnostic:
If you just got started, you might not need all these tools yet. In that case, a whiteboard and a number of post-its are sufficient to create your first Kanban board. This...