How to stop the sreen from turning off on the Nikon D3100?

I have just got the nikon D3100 and i'm loving it but the screen keeps going off after like 6 seconds.
is there a way to keep the screen on for longer?

also how can i take light lighters when the shutter speed is at 1/2000 - 1/4000 because when i try it ends up really dark?

The manual. The right setting should be in there that will keep the LCD on longer before it starts saving precious battery power.

To get light streaks, set shutter speed slower. Try 1/15, 1/8, 1/4, 1/2. 1 sec or longer.

What does light lighters mean? If you mean brighter pictures with a high shutter speed lower aperture and bump up iso a little.

Settings should help with the LCD turning off however, remember the longer it is on the more the battery power is used.

Regarding dark photographs, two things to consider, the light you are shooting in, is a flash being used or can it be used? And the second thing to consider is aperture settings available or is another lens needed with larger aperture capability?