In combat, it's better to plan a solid strategy than to try to deal maximum damage as soon as possible. Your party will often find itself outnumbered, and enemies may have advantages the player may not (yet) have.
Try to identify the main threat in the opposition. For instance, if there is one mage that keeps on healing his allies, or even insists on resurrecting all his fallen friends, direct as many attacks as possible towards him.
Try not to hit too many different targets at once. Focus on getting one enemy down instead of hurting many. Two trolls with 1 hit-point each still deal full troll damage twice. The damage dealt to these two trolls would have better been directed toward one troll.
Use the environment. For instance, you can position yourself so that archers may not hit you, or have to move before being able to hit you. Or you can create choke points so that not all of the enemy’s forces can target you.
Be on the lookout for items that can help you in battle. Throw things at your enemies, destroy items around them so they must take a longer path, explode oil barrels, etc.
