Take one look at a car, clothes and your other non-decorative things that you live with, if you do not have a slightest idea where you can start but you want one place where you will be comfortable with a feeling of being perfectly at home. Many things, which you like yourself to surround with, can surely be a color inspiration of yours. You should avoid colors, which do not work for yourself.
Just like how your favorite colors give you a feeling that you are at home, these can give an idea to you about what you should not do. In case, you look bad in orange for example, then you might like to do away from that when you are decorating your favorite room. Lounge on one blue sofa in case you feel better in blue. Otherwise, if you like the gunmetal-gray shimmer finish of your coupe, translate that to stainless steel tiles or appliances in kitchen of yours.