Instructions
Direct workers to farm and harvest food in the tiles around your city. Your population needs food to stay happy and to increase, as starvation decreases your city's population.
Build settler units and send them out of your city to establish new cities. As you gain new territory, you'll want to have enough cities to work the land while still having protection against invaders.
Increase your city's food output through granaries, harbors and aqueducts if your food production is falling behind. Build the Hanging Gardens in your largest city to increase the population by 50%.
Build a courthouse to increase the amount of workable tiles surrounding the city. When you increase the workable tiles, your workers can bring in additional food for the population.
Switch workers to production once you have stable food levels coming into your city. Production allows you to gain gold and other resources needed for your cities and armies. The higher your population grows, the more culture you gain, so you will find Great People arriving in your highest population cities.