I have a big screen TV projection 56 in the color is starting to turn blueish a bit how can it be fixed?

When a TV screen tints a weird color, usually the screen is going bad, and it is usually less expensive to just buy a new one than have it repaired.

When the color changes it may also be from a magnet

How old is your TV? If it is a rear projection CRT TV and a non sheilded speaker with a magnet, or other magnet came close, that can cause picture anomalies like what lawnman mentioned. Is the blueish color in one spot, or is the entire picture becoming blue? Again with CRT's it could be going blue because one of the other guns are starting to fail which would be due to its age. And replacing the TV would be cheaper. If it is a LCD or DLP rear projection TV, it could be failing as well. Or would there have been a chance of someone messing with the color settings? Sometimes tv's and monitors have color temperature settings between warm and cool, cool being generally more blue.