If you'd like to change the image in your course banner, follow these steps.
Step 1: Go into your class.
Step 2: Select the three dots in the top right corner of the current banner.
Step 3: Select 'Change Image'
Note: DO NOT select 'Remove This Banner' under any circumstances. If you remove the banner, it will take a different process to bring it back.
Step 4: You will be brought to this screen.
Type in what sort of image you want for the banner.
Step 5: Select which image you think fits best with your course and click 'Use this image'
Congratulations, your course banner is now changed.