How do you sing whatcha say?

Here are the lyrics to the chorus of "Whatcha Say" by Jason Derulo:

[Chorus]

Say, wah, cha say? (What)

Cha cha, nah say? (Na say)

Wah, cha? Wah, cha? Eh! Wah, cha say?

Cha cha ah nah, say yeah

Repeat as desired!