Upon your guild reaching level 8 the Mill will be unlocked.
The best way to get Guild Coin, your team will be guarding a stock pile. Other player may find your stock pile while search in the Plunder tab. Every lose will reduce the amount of Guild Coins received and the end of the Order. Orders can be upgraded to give more rewards, up to a next of 6 stars.
You and your guild mates will donate coins to upgrade the Mill giving you more coins and Guild Coins per Order.
You will scout for another players Order and attack their team, if you win you make of with some of it. Stamina recharges every 2 hrs to a max of 10. The defenders teams power will be displayed after completing your Scout.