I tried Overtone on a whim, and figured if I was gonna go, I was gonna go big, so Extreme Purple it was & remains to this day. (I did a brief detour into the green family, a sort of tip o' the hat to St. Paddy's Day, but discovered green isn't really my color.)
I moved into my 6th decade with purple hair, and love every minute of it. I get TONS of compliments from random strangers, and have preached the gospel of Overtone to each & every one who asks, "HOW do you do that?" I've even sent Overtone overseas to a Polish friend who always wanted pink hair. (She loved it & looked great!) I started out having a neighbor help me with the application, but I just do it myself now. Pro tip: keep a damp cloth to wipe off any color that gets on your skin, and you'll definitely want to scrub any that drips onto sinks or other surfaces as soon as possible.
Really, really love this stuff! Highly recommended. But y'all probably want blue or red or any other color beside purple; I got a lock on that one ;)