Solo PVE Technique
Druids have good survivability in one-on-one PVE combat, provided you choose your targets effectively. Pure melee classes, such as opposing humanoid warriors, can be troublesome for druids, as you won’t have the kind of armor and health required to really stand up to a beating, at least not in your humanoid form; you may want to switch over to Bear form when going up against high-damage/high-health targets.
While in humanoid form, though, there’s a very basic series of steps that will see you through most combat. After spotting a target, you’ll get its attention with Wrath or Starfire (long-cast nukes), follow up with Moonfire (insta-cast DoT) and perhaps Faerie Fire (insta-cast armor reduction), then go melee. You can reduce the amount of relative damage you take both with Thorns (which deals damage to your enemies each time they attack you) and Rejuvenation, an insta-cast regeneration spell. All of this should let you enter combat while the enemy has a bit of life taken off, is bleeding extra because of the Moonfire DoT (which you can recast as often as you like) and because of Thorns, and while you’re gaining life because of Rejuvenation. This should help balance out the fact that you won’t deal as much damage and have to wear lighter armor than pure melee classes.