You can add friends to play with in the following ways:
1. Add random friends using the Friends menu. Every 8 hours the list of random friends is updated, and you can send a request by selecting a friend you want to add by pressing the Add button. You can send requests to 4 people at a time and wait for the next 8 hours for the list to update or spend 5 diamonds to update it immediately. Note that you have to wait for these players to accept your request. Only after that you will be able to visit theirs Albions, send gifts and communicate with them.
2. Add friends in the game using the game identifier (Support ID) that players post at the official game community on Facebook here: https://www.facebook.com/355886191166202. To redeem a code, go to the Friends menu → Invite Friends → Add Friends by ID. In this case number of invitations you can send is unlimited.
You can also find your friend code in the tab mentioned above.
3. Add a friend from Game Centre or from Facebook.