Creating an alliance
You can create an alliance when you have an embassy level 3. Then inside the embassy, click "Found Alliance". Enter the Tag (short name) and full and click save.
Sending alliance invites
You can invite people into the alliance if you are alliance founder with full rights to the alliance (default for the founder) or the alliance founder has granted you a right to invite people into the alliance.
You have to write the name of the player exactly as it is to the "Name" box and confirm by clicking "OK". If the invitation was sent successfully, the game will show "An invitation has been sent to …." and the invitation appears to the "invitations" table.
After that, if the player accepts the invitation, he will join the alliance.
Joining an alliance
You can view local alliances in your area from the embassy level 1 in the find alliance tab. You can click the alliance name to find out the leaders and send them a message to ask for an alliance invite.
You can join an alliance when you have built an embassy level 1, and have an invitation to the alliance from the alliance leader.
Once you have been sent an invite you will receive a message from the Ambassador
You can then accept the invitation from inside the embassy.
Leaving an alliance
You can leave the alliance earliest 24 hours after you joined it. You cannot be kicked out of the alliance during this period as well.
Note that this timer was introduced in May 2022 and does not exist on gameworlds that started earlier.
Other than that, you may leave the alliance any time you want, using the alliance options page.