Dual screen (duplicated)

[Th3Alchemist]

I have a presentation in some days, where I'll have to hook up my laptop on a projector and I need to give a presentation where I speak and use my laptop, and so the viewers can see my screen on the projector. But I can't figure out how to set it up correctly.

I got NVIDIA drivers installed. And I try to set it on duplicated screen mode, but all I get is separeted desktops views.

Pease help.

Note: I run Ubuntu 12.10 with Nvidia drivers installed