Over the past few years I have become a dab hand at camouflaging my grey hairs. It is essential though to always wear gloves to protect your hands and nails from chemical reaction and staining. I also apply a layer of E45 around my hairline to protect my forehead. I am sure Vaseline would also be a good alternative.

I think dark dyes actually are very dark and stain easily because they have to cover up ligher hair. Lighter colors (like blond) use peroxide our something else to change the color of the actual hair, so it doesn't stain your skin. You are right though, using dark dyes without gloves is askng for a lot of trouble!