(RedShelf version)
Where do I find my materials? Your materials will be located inside of Canvas, under a tab labelled "My Course Materials". See screenshot below:

If you see a book tagged as "ebook", these can be opened and read. For the books that are tagged "Physical" there is a link to purchase from www.cubookstore.com.
Click the "Read Now" button to read the eBook:

I do not need these course materials, how do I opt-out? You can easily opt-out by going to: Canvas on a computer or a web browser on a phone (not the Canvas app) and click the "My Course Materials" tab. Open each digital item and you will see an "Opt Out" button (see screenshot). If you opt-out please be aware you will also lose access to the materials after the opting date. For courses where you are using an ebook and courseware like MyLab, please check with your instructor to make sure you will not need the courseware before opting out. You will need to use a web browser to opt-out rather than the Canvas app.

Second screen of opt-out: click the "Continue" button

That's it! You'll briefly see a message at the bottom of your screen confirming you've opted out of that material.
Have a question about the ereader? Please contact RedShelf: https://solve.redshelf.com/hc/en-us/categories/115000384354-Student-Customer-Support
Have a question about how to launch courseware such as Cengage Unlimited, MyLab, MyLab and Mastering, Connect, etc. ? https://solve.redshelf.com/hc/en-us/categories/115000384354-Student-Customer-Support
Have a question on accessing your ebooks, courseware, or physical materials? Accessing "My Shelf" Through Canvas :https://youtu.be/vy2vrczinQY
Managing Opting into Day 1 Digital Access : https://youtu.be/08yLt7D5iho
Accessing Your eBooks in "My Shelf": https://youtu.be/LWMjOkjiya4
Accessing Courseware from "My Shelf": https://youtu.be/PmMNMJynmk0
Accessing Physical Materials: https://youtu.be/7TZpyjWzF_o
Getting Help: https://youtu.be/z52agF2b0Fc
Billing Questions? Please email assist@cubookstore.com for billing questions.
Question not covered here? Please email assist@cubookstore.com and we'll help you out!