Select "Add channel" and confirm the selection when prompted.
After you have added the channel, go ahead and open it. If you have not already registered for a Cineverse account, select "Register for FREE" to enter the registration process. You can also upgrade your membership to VIP once you have registered.
If you already have a Cineverse account, select "I have a Cineverse Account" and enter your username and password.
You are now ready to watch Cineverse on your Roku!