i found a shortcut to this method. only do the last part of step 4 and it will still work!!!
1. Queue for BG's as a frost mage.
2. When a queue pops, summon a water elemental.
3. Enter the battleground.
4. During the battleground, summon the water elemental
5. AFK out of the battleground.
6. AFK to log out.
7. Log in, you should now have an eternal water elemental.
move to elite asap