This can be found on the help page.
http://www.conquerclub.com/eticket/index.php19. Can I let another player take a turn for me when I am away from the game?
Players are allowed to account-sit for others as long as they are not opponents within the game. It is common courtesy to announce in game chat that another player will take your turn(s) during your absence. Babysitters should only do what is necessary to take the turn(s) and should not interact with the community, start or join new games (except for ongoing tournaments). Furthermore, you should only take another player's turn if they are in danger of missing a turn, not for the purpose of gaining a tactical advantage.
The sitter doesn't have to wait for the last minute to take a turn but it is discouraged for the sitter to take multiple turns in a 24 hour period.