- Help other players! For example, blueprints can be earned if you regularly help your neighbors and friends from the guild. Make sure that the decorations of the other players look fantastic or motivate their populace and you have a decent chance at getting a blueprint. Which blueprint you receive, depends on what age the supported building comes from.
- Plunder other players! It is almost just as good to attack other players and earn a blueprint. You will have to plunder the buildings in the desired age for the building you wish to construct. With a little bit of luck you could find yourself with some wonderful blueprints after a round of plundering.
- As a reward for your help with the construction of great buildings of other players. You will have to give enough resources so that you are among the best helpers when the building is completed.
- You can also trade any blueprints that you have doubles of. However, you have to trade two blueprints in order to get one in return. To do this, open the construction menu of the great buildings and select the blueprints which you would like to give up and then click trade.
- By using premium currency, if you already possess one of the nine blueprints.
Source: Game homepage