Colour

Right. So I've bought some hair dye! It's light brown with an auburn tinge - something nice while still being safe for work. The only thing is, I've never ever dyed my hair before and the instructions have confused me a little. I presumed that one washed one's hair the day of dying, but the instructions start by telling me to wet my hair without washing it. So does that mean wash it, dry it, then wet it, then dye it? Or does it mean have dirty hair before dying (and if so, how dirty)? Confusing! I beseech those of you who have dyed your hair to answer this riddle for me. Also, the packet heartily recommends doing an allergy test, but I'm not sure if I can be bothered, or if I really want to leave a spot of colour behind my ear for 48 hours without washing or touching it. So how many horror stories have people heard about people who skipped the allergy test? How bad can it be? Will I really be risking that much if I skip the annoying preliminaries?