How to change picture format to RAW on my DSLR?

I own a Nikon D3100 and I want to change the picture format on my camera so that my photos are shot in RAW (or NEF in Nikon cameras)

I wish I could help, but I only have a Nikon slr. In canon, you go to the menu and look the for weird L symbol that represents jpeg. Try that with your nikon.

What does your user manual say?

Look on pages 64 and 65

Do you understand that you will need to do post processing if you shoot RAW?

Nikon D3100
http://imaging.nikon.com/...slr/d3100/

Manual Guide >
http://support.nikonusa.com/app/answers/detail/a_id/16910/~/user's-manual---d3100---guide-to-digital-photography

pg 64 Image Size and Quality:

1 > press [i] Information, or Place the cursor in the information display. [i],

2 > Display image quality options.
Highlight the current image quality in the information display and press (OK)

3 > Choose a file type.
Highlight an option and press (OK)
To return to shooting mode, press the shutter-release button halfway.
.

1. The information is plainly explained in the camera owner's manual.

2. You should easily be able to ascertain how to do it even without the manual.

3. If your skill level is so limited that you can't even set the camera to RAW, then you most certainly do not have the skill level to know what to do with a RAW file anyway.