hi gmollster, and welcome to the forums

note: i put single quotes (') around strings... do not include them

first, pick a key that you will use to tell your clone to follow. let's assume you used '='

next, clear the '=' action bar slot on both wows. while you are at it, clear the '-' slot as well

on the clone, hit escape and select 'macros'

click 'new'
type 'follow'
select an icon
hit 'Okay'

your cursor is now in the edit field for the macro. i will assume your main's name is 'joe'... change accordingly. type this into the field:

/follow joe

now click and drag the icon to the '=' action bar slot.

you should repeat for an assist macro. changing the name to 'assist' and typing this for the macro:

/assist joe

i would put the assist macro into the '-' slot

hit the 'Exit' button on the 'Create Macros' window

now click on your main's screen. hit '=' and your clone should follow. hit '-' and your clone should assist your main

i hope that helps. let me know how it goes.