What did you base your spell off of? there is no spell that is activatable that isn't based off a spell.
Pretend you modified war stomp. The action would be
Issue order with no target
Order unit to Orc - Centaur Warchieftan - War Stomp.
I cannot explain it any clearer, it DOES NOT REQUIRE VARIABLES. AT ALL.
You select THE SPECIFIC SPELL that the spell YOU made is based on, and you find THAT SPELL in the list Blizaard gives you.
--donut3.5--