New to multi boxing. Question about fastest way to get to level 15

I've got 2 60's on my main account, a mage and druid. Just setup a new account to play with multi boxing. My plan is to dungeon grind, stocks, sm, zf, BRD, dme to powerlevel some toons.My question is, what is the most efficient way to get my characters to level 15, so I can start dungeon grinding.Thanks