Ok,
I thought this was such a simple thing to do but its just not doing it.

I'm trying to change the page orientation of the photoshop drawing canvas from Portrait to Landscape.
So I thought File > Page setup and then clicking the Landscape button...is that wrong?

It just doesn't do anything. The white drawing canvas just doesn't rotate at all. I can use the rotate view tool but then of course when you use text etc thats now at a strange angle.
Any suggestions or am I just not getting it