Think about other commands you use with your dogs.
I train my dogs to ring a bell with their paw when they want to go outside. With my first dog, Brianna, "ring the bell" was an easy command for her to learn.
With my second dog, Annabelle, I think "ring the bell" to her sounds too much like her name. When I say "ring the bell," she just cocks her head and looks at me.