Instructions
Avoid stockpiling gold, as unused gold does no good for your city and relative power. Gold should always be used for the next upgrade for troops, buildings or extra resources. Upgrades are especially useful because they make your city stronger and help you more easily repel attacks from invaders.
Invest in defensive structures, especially storehouses, watch towers and sanctuaries. The sanctuary is the final defensive structure in your city, which can shelter troops without being destroyed. Storehouses fill a similar role for resources, especially when combined with the "Shrinking Powder" which can vastly increase the storage capacity of your storehouses.
Build up your horde of defensive and offensive troops, with an emphasis on defensive troops, for city walls and buildings that can be garrisoned. The watch towers are especially useful for learning the numbers and composition of attacking troops in order to counter them in kind with your offensive troops.