Click on Classrooms in the top left of the window
The page should default to the Classrooms tab at the top
Scroll down on the page and locate the classroom you want to modify in the list, to the right of that class are the options for Change Step Order/Style and Edit Classroom
Click on Edit beneath the Change Step Order for your class. You can re-order the steps by dragging and dropping them into the order you want.
Click on Edit beneath the Edit Classroom to modify any of the settings there.