In order to create a multi-day session, you first need to create a session or open an existing session plan. You will find an ‘Add day’ button under the session’s name in the header.
Please bear in mind that creating multi-day sessions is available for users on a Pro or Team plan, and only for the owner of the session. Collaborators (with editor or viewer rights) are not able to add (and delete) a day to a session.
When you click on this button, it will result in the following:
Your initial single-day plan becomes a day-session named ‘Day 1’
A new day-session named ‘Day 2’ gets created
You just need to click on the day you want to work on to begin creating your first blocks. If you want to create further days, just click on the ‘Add day’ button.