I use to dye my eyebrows at home.
The method I used was to first take peroxide, pour some in the little cap, then use a q-tip to carefully apply it, you might want to squeeze the q-tip first to remove excess peroxide and have some tissue at hand in case it starts to run.
I would go over my eyebrows a few times depending on how light I wanted them and then wash them when I was done.
I would also sometimes dye them afterwards using the leftover dye from my hair colour kit, also applying with a Q-tip.
You just have to be careful.
I just had mine dyed to match my hair when I was at the salon the other day and to be perfectly honest I am much more careful then my hairdresser was.
It is not illegal to have your brows dyed in the States and I think the same goes for lash tiniting, though it is widely thought that having your lashes tinted is dangerous and I would never do it.