Open the text you would like to edit
Go to the page you would like to edit
Click on the Edit icon
The Edit icon is under the page titleĀ
Hovering over this icon will display an "Edit this page" message
The "Edit book page" window will appear
Edit the page's content in the "Content" box
Edit the page's title in the "Title" field
Click Save
The "Edit book page" window will close
Your section will be edited