How can I add perks to the perk library?

From your dashboard, click on 'My Account' located at the bottom left.

Next, choose 'Manage Settings'

Then, select 'Membership Perks Library'

Click on 'Create Perk +' to start adding a new perk.
Under 'Create New Perk', type in the name of the perk you wish to add.
After typing in the perk name, click 'Save Perk' to confirm

The perk will now show in your perks library list.
To automatically add the perk to any new membership, simply click the star next to the perk you want to assign