If you have created your own Alliance, the best way to find players is to be active in the chat channels, in particular, the Alliance Recruitment Chat.

You can find the Alliance Recruitment Chat by pressing the "chat" box at the bottom of your screen, tap on the gear icon, choose CHAT ROOM --> ROOM TYPE --> ALLIANCE RECRUITMENT. 

It is important to remember our Chat Rules & Guidelines and not to "Spam" any chat channel with Recruitment Ads. 

You can also find active players on our Small Giant Forums, Alliance Recruitment page https://forum.smallgiantgames.com/c/alliance-recruitment