Your computer advisor for trade is activated by clicking on the human face icon at the upper left part of the screen. The icon changes to a computer confirming that you have given control of trade to your advisor.  You regain control by clicking on the button again.

One good way to learn about trade is to turn on the advisor temporarily to see what the computer would choose to do. Then you can restore human control and make any changes to the computer’s orders you feel are necessary. 

Often, on the first turn of the game, the computer will choose not to bid or offer anything.  Because your Empire has no trade consulates with Neutral States, and because your warehouse is fairly well supplied, the computer sees no reason to conduct trade.  You might want to trade on the first turn if you can look further ahead  than your advisor and see upcoming shortages. 

Once you establish trading relations with Neutral States or Tribes, or once you begin expending the commodities in the warehouse, your computer advisor will enter bids and offers if you give it control of trade.