I heal with separate keys than my dps. I use keypad 1-5 to heal the player that corresponds to that number on my screen. So for keypad1 my macro is

Code:
/stopcasting [harm]
/target tankname
/castsequence reset=6 Riptide, Lesser Healing Wave, Lesser Healing Wave, Lesser Healing Wave
and for keypad2

Code:
/stopcasting [harm]
/target playername2
/castsequence reset=6 Riptide, Lesser Healing Wave, Lesser Healing Wave, Lesser Healing Wave

Then I just use my left hand for all the tanking and dps stuff and right for healing and special macros on the keypad.