Gahhhhhh! I love your nails! :D How do you get your lines SO thin?!

Hiiiii!!  Thank youuuuuuu!!
I actually use a very thin and short paint brush (that I purchased from an art supply store) and I trimmed it down myself, to get the hairs to an extremely fine point at the tip.  Also, I use a brush with real hair; I am not sure if it makes a difference, but it might!  :D