basically you can do two things

either you have a separate macro to set focus for all your clones and then make all your macros /a [target=focus]

or

you can insert the name of your main and simply make it /a [target=Brain] or /f [target=Brain]


examples:

Focus method..

Code:
/target Zorgom
/focus
this one sets the focus as that character on all clones
then use
Code:
/target [target=focus,help,exists]
/follow
/assist
/stopcasting
for follow

or

Code:
/target [target=focus,help,exists]
/assist
/cast whichever spell you like

using the non focus method:

Code:
/target [target=Zorgom,exists]
/follow
/assist
/stopcasting
and

Code:
/target [target=Zorgom,exists]
/assist
/cast whichever spell you like