You chose eyebrows for today's topic. This is one of my many favorite things. I started out with straight lines across my face, to too thick and cavemanish, then on to toothbrush shaped, then tadpoles, and at some point I got it right! I'm sharing that last one with you. ;)
You can use a pencil or an angled brush (I prefer the brush) and a matte shadow that matches your hair color or is within 2 shades.
You want to start by marking the 3 main points of a perfectly shaped brow. First, angled at the inner corner of your eye.
Then mark at a 60 degree angle from your pupil.
And the 3rd mark is at your outer corner at a 45 degree angle.
Now the tricky part: filling them in. Thickness is really up to you. You can do really thick like Jennifer Connely:
Or really thin like Pamela Anderson (not recommended):
Or in the average range like Scarlett Johansson:
If using a pencil, make sure you brush your eyebrows in a sweeping upward motion before filling in. When you start, make an outline (do not just start filling in the middle), that way if you do not like the shape, you can wipe it away easily. You can also buy eyebrow stencils in the beauty section at any drugstore. That is how I learned.
Once you are happy with the outline (don't get frustrated if it takes a couple tries), start filling it in. Last step: Admire.