About 6 and agree about the lack of home hair-dye. First time I did that was with Inecto Hint of a Tint, a semi-permanent (of course!). Copper. I didn't realise that my hair/skin was of the variety that ALL the colour takes in the first 10 seconds, so washed my hair in normal fashion (head hanging over the bath) and tipped the lot on the back of my head, then massaged it through my hair and left it as suggested.
Being 14 at the time, sometimes I still wore my hair to school in 2 bunches - I did this a couple of days later and my friends kindly pointed out the MAGENTA patch I had in the middle of the back of my head!
Done the fringe ones too. And the mascara-stick in the eye, and the runny mascara. Oh, and the sticky lipgloss. And probably lippy on the teeth, although no photographic evidence of it.