The mantra, or chant, or chantra, or whatever

We went with the tune of a simple nativeish pagan type chant, you know the more or less one two one two, emphasis on one, kinda beat? The chant we modeled the tune and rythem off goes (spelling attrocious no doubt)

Wichitaw Dooya
Doo ya Doo ya
Wichitaw dooya
doo ya hey

and theres a varient on the verse for the second one, but if you recognise it you should be able to get the tune from that, if not, just imagine a neo-pagan pseudo-native chant and go with

Hey-a, Kay-I
Grey-eye, Our Eye
See ya, Hey-A
Yell out Hey!

Also, given the simplicity, it probably works into other chanting styles if the whole pseudo-native thing doesn't jive with your ritual style.