3. Make sure your formation is balanced
Whether you're preparing to attack or defend, you should always have a balanced unit. At least your formation consists of melee fighters (Swordwrath, Spearton, etc.) and range fighters (Archidon, etc.).
Fighters in the front position deal damage when fighting head-to-head with enemy troops as well as their statues, and long-range fighters protect from behind. That way, your chances of winning are greater.