Change the opt-in settings via this option in the main menu:

From here you can customize various elements:

1. Default Setting
Select ‘Instant Access’ if you want people to access your resources without entering their contact information.
2. Opt-In Form
This is the form that will be shown when someone clicks on a resource in your library.
3. Confirmation Email
This is the email that will be sent to a subscriber after they enter their contact information.
4. Email Integrations
Connect to your preferred email marketing tool so that new subscribers will be automatically added to your workflow.