I saw my first white hair when I was 24, and by my early thirties, I was touching up the area around the part with a magic marker.
I got away with that for a few years, but well before I was 40, I was using drugstore hair dye on the roots, and I did that until I was 52, and finally broke down, went to the salon, got my waist-length hair cut to just about shoulder level and layered, and received a lecture on non-permanent color, which I get at Sally's, and hope that one day I will be able to lighten my naturally black hair to coffee brown, with aubergine highlights.
And yes, the first sentence is all that was really necessary to answer the question, but we all know that I am a person Living With Brevity Impairment.