I’m looking to try the trendy, icy shades as a hair color. What kind of color do I need for that look?

Double Process color is typically used when lightening hair by more than two shades, like changing from a dark hair color, like brunette, to a much lighter, blond color, for instance. The process involves actually stripping natural hair color (or color from previous dye jobs) first and then adding colored pigments into the hair to create the desired shade. This is definitely a process to leave to a professional.