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Use the “Manage my Contacts” feature on your NOOK device or account to enter friends you are interested in sharing books with. Follow the prompts to add  new contacts by entering in their names, email addresses, and any other requested information. Once you have entered in a friend’s contact information, tap the “Invite as NOOK friend” option. This will send a message to the friend to accept the friend request. The message will also share information about setting up a Barnes and Noble account, if your friend does not already have one. You can advertise your lendable books by going to the Social settings on your NOOK and selecting the option to do so. Check the option to “Show all my lendable books to my NOOK friends.” That way, your friends can browse the books you have that are eligible for the LendMe program, and request them if desired.

Summary:
Enter contacts to share NOOK books. Request an invitation. Use the Social settings feature to share books.