Watching Enemy Casting Animations
Each spell school such as shadow, fire, and holy has a distinctive spell graphic that is easily recognizable. By watching what animation displays when the enemy is casting, you will then know how to counter it. On the other hand, the counter to that is to cast a spell from a different school of magic to fake your opponent out, then switch to the real spell you want to cast.

PvP Realm Survival Tips

Understand the Region/Zone Types
On PvP realms, a given zone can be either friendly, contested, or enemy territory. Each zone type has its own rules governing PvP eligibility. If you're in a contested zone, you can be freely attacked by the enemy, and vice versa. If you're in a red (enemy) zone, they can attack you but you can't attack them unless and until they strike first. If you're in a green (friendly) zone, they can't attack you unless you attack them first or you are flagged for PvP. Learn more about PvP zone rules.

Pay Attention
Surviving on a PvP realm requires constant vigilance. Look over your shoulder any time you're in a contested area. Know that your quest plans could change any moment because at any point, a battle with the enemy faction could occur. If you're not seeking this kind of tension, consider a normal (PvE) realm instead of PvP. It's not for everyone, but you'll find that most people that enjoy playing on a PvP realm love the exhilaration of never being safe. It takes patience, skill, and the willingness to keep up with PvP strategies. It might mean more reading and studying than playing on other realm types, but if you're reading this, chances are you're up for it.