Henna on skin

So i'm ready to henna and I've gotten over all the fears lol, then I realized that since henna's a dye, it could stain my neck and forehead.
I really really don't want a red forehead and neck/ears, so I just want to check if its happened before and what to prevent it!
Thanks ladies

No, I haven't found that it's stained the skin on my forehead or neck. It's always been easy to clean off. However, watch the fingernails, those are very easily stained.