Wow! This is too beautiful. I came across this picture on A cup of Jo, one of my favourite blogs. I would love love love to be able to do this look for night out. Very chic, very sexy. Here's a quick how to:
Tip 1: Use a light eye pencil to create a sketch of how your "wings" will look. This way, you can easily make corrections by erasing with a Q-Tip. The line should start as thin as possible and grow fatter and fatter toward the outer corner of your eye (you'll trace over it with liquid liner later, and many liquid liners are shaped like calligraphy pens, which'll help you nail the perfect thickness). How far your wings go is up to you (it depends on your eye shape, face shape, personality), but keep in mind that a few centimeters go a longway, and less is usually more.
Tip 2: Step away from the mirror for a couple minutes, then come back. You should be able to tell right away if your eyeliner looks symmetrical on both sides. If it doesn't, erase and adjust. If you really have trouble getting the angles of your wings to match up, trace a business card--that's a trick Gwen Stefani's makeup artist, Kathy Jeung, told me once, and somehow it really does help!
Tip 3: Trace over the pencil with liquid liner, resting your elbow on a table to help keep your hand steady.