This may technically be for sketching, but the instructions are the same for filling in missing eyebrows using makeup. You want the brow pencil to look like little hairs so you don't resemble a cartoon character when you're finished!
How to Draw an Apple with Colored Pencils. A step-by-step image of a colored pencil #artlesson by Derrick Rathgeber. Click the image for full details instructions on my blog page. http://derricktheartist.blogspot.com/2013/08/how-to-color-delicious-pink-lady-apple.html