If you are using a projector or other large screen format such as television screen to show your presentation then you can try pressing "Fn" (function key) and "F7" to bring up the settings for the viewing on the separate screen and have it as an extra screen and have the presentation showing on an 'extended screen' which is independent of your actual computer screen so you could have the presentation open on both screens with the upcoming slides on one and the actual presentation on the other.

Hope this makes sense, I'm not very good at describing,

Mulveriser