I have red hair and it loves to fade really fast. Someone told me to put my color in my shampoo to keep your hair red. Is that true?

Most hair color have a shelf life after its mixed that's very short. Too short for putting in your shampoo.

You should get a good color care shampoo and conditoner. Many different companies make them. I really like the matrix biolage. I think that there are some companies that make shampoos for specific colors like red, brunette, blonde.