hair metal band needs someone to vocalize the lyrics at practice

We need someone to vocalize the lyrics during our practice sessions so that we know where we're at.
A lot of the cues are vocal, it's hard for us to know where we are at without someone "singing" the lyrics.
You don't have to be a professional singer or even have a good voice, just vocalize the lyrics at the right spot, until we find a proper singer for the band.
We practice at Fresh Ground Sound in Ventura.
Whitesnake, Van Halen, Dokken, Ratt, Survivor, etc.