You can turn a regular task into a recurring task from anywhere by clicking on the edit task icon (cog) and then clicking the recur icon (curved arrow) at the top.
This will open the recurring task dialog, where you can set the recur pattern and other options.
Creating a recurring task from the recurring items menu
In the menu at the top right you can navigate to the "Recurring items" overlay, where you can see all your recurring tasks and projects.
From there you can create recurring tasks by clicking the button on the top left.
