Just getting started myself, But I can explain what I have done.

Running two instances of WOW on one PC , I am using Keyclone. So easy to set up, worth every penny man.

Next, On my main, I will have for example this macro.

/Invite (character name)
/ffa
This simply invites your second character, and FFA sets loot to FFA

on the second tune, I have

/follow (character name)
/assist

Follow makes him follow your main,

assist, assists your main.

Now you can get tricky with it, but that's later on down the road.

I then put that Macro on the 1 slot for every slave.

FOr two, I put the main attack , spell, etc.

Then when I hit 2 for example, it will use everypersons 2 in the bar.

I'm sure as I go past twenty,I'll ad more difficult macros to the bar, But that should get you started.

Stephen