Play Single Player -
Random Map ,With Difficulty - Easiest, With At Least 
Other Players - 3, With Reveal Map - Normal, Starting Age - Standard,
Victory - Standard & Tick the Team Together, the All Techs & Don't tick 
Lock Teams.

At the starting of the game messages will appear like that -
"X Changed diplomatic stance with you to neutral." (x= Other players)
Then Open the Diplomacy(ALT-D) Screen,Change other player stance to neutral.
Thus in next age when you have a market,messages will apper for 
make ally by giving some 100 resources of food,wood,gold or stone.
paiding so you will be able to make ally with other players.