Set up your skills like this, put the rank where I have mine, then make a macro... For example:
/cast Shadow Bolt(Rank 9)
/cast Corruption(Rank 6)
/cast Immolate(Rank
/cast Curse of Agony(Rank 7)
Now here comes the part that need's fixing. We all need to brainstorm something that puts a 3second wait time between each cast. When you try it as it is you will recieve a message sawing "Anther action is in progress." so I know it will work..
Sorry if it's in the wong section I didn't know if should go in General WoW, or Exploit's, so I decided to put it here beacuse Blizz dosen't allow this, therefore you are exploiting the situation.. (Just wanted to avoid flame xD)