Building
Begin building everything possible. Make sure to use the free speed-ups that are available for low level buildings. Try to get everything in your kingdom to level 3 before timers get longer. After your Castle reaches level 4, begin building more homes, farms and other resource generating buildings, and level them up as well. Create a balanced setup, with good attack, defense, and structures.
Factions
The Sultan has 5% squad size bonus that allows you to bring more power into battle. It also increases research speed by 10%. Its Hashishin unit has retaliation as a special skill. The King has a 5% boost for marches which favors a more active and offensive play style. They also have a construction speed and iron mining boost. Its Teutonic Knight unit is very powerful. The Tsar has a 10% boost to training speed. They also feature an extra champion experience point bonus. Its Boyar unit is also useful.
Hero
You can improve your Hero's Warfare, Income, and Progress. Because each of them has a very deep skill tree, you cannot unlock and maximize all the skills. Decide on a skill tree to be your focus.
Resources
Complete quests when actively playing. Also participate in adventures, leaving the longer ones to be completed when you are away from the game. Locate unoccupied resource sites on the map and send troops there. Consider doing this during frequently early in the game while you are under protection. Train a lot of troops to farm inactive Empires for resources. Attack them repeatedly and send marches to resources.