I was told if I do a lot of riding in water I should drain water from lower unit, how do I do this?

[2015 Z Force 800 53/Trail EPS]

I was told if I do a lot of riding in water I should drain water from lower unit, how do I do this?

No such thing. You have a differential in the front and a gear case in the read. Those may bet water in them at times. They have drain plugs. See your manual.