How to adjust the exposure indicator back to 0 in d5100?

I've gotten my nikon dslr just yesterday and i've accidentally set the exposure indicator too dark. Its in manual mode. How do i change it?

You'll have a pdf.manual on one of the discs that came with the camera, or a paper copy. If you don't, download a copy of your manual from Nikon (free).

Reading the manual is the only way to learn how to correct these little blips, and how to avoid them in the future, and if you aren't willing to sit down with the manual and work it out for yourself, you've wasted a h*ll of a lot of money on a camera you'll never be able to use properly.