Colonization

You need a fleet containing at least 1 Outpost Ship or 1 Colonisation Ship. The Outpost Ship is much cheaper so it's suitable during early game.

Colonization with an Outpost Ship

The Outpost Ship is more a flying building then a real ship. As soon as you colonise, the ship lands, and becomes the outpost you see in the finished buildings list on your planet building page. When you deploy the outpost ship, your new planet gets these resources and buildings to start:

10,000

Metal

8,000

Mineral

2,000

Food

1 Metal Mine

1 Mineral Extractor

2 Farms

1 Solar Generator

Colonization with a Colonisation Ship

The Colonisation Ship is very expansive and requires a Space Dock. As soon as you colonise, the ship lands and is disbanded to create your colony. Its advantage is that your new planet will already have:

150,000

workers