If you are already in the Composer, first go back to your Dashboard by clicking on the button in the top right of your screen 
, and then clicking Dashboard 
.
Once you are on the Dashboard, click on the Yearbooks tab on the left. Find the yearbook that you want to edit, then click on the down arrow 
to the right of the green Yearbook button. Click on Project Settings from the dropdown that appears.
When you are in the Project Settings, at the bottom go to Number of pages the book needs to have, and change the number of pages. *Pages have to be in multiples of 4.* After you change the number, click Save and the new pages should be in your Book to use!
