Eyeliner can be tricky sometimes, especially winged eyeliner. I've used the Beauty Parlor to explain the best technique for real life so your eyeliner matches both eyes.

Using liquid liner, start from the tip of the wing (making sure it has a fine point) draw a neat line to the outer corner of the eye.

(I have used blue eyeliner so it is easy to follow, but you would use the same black liner.)
Start from the tear duct and across the eyelid, joining the wing.

I have found this to be the easiest way to apply my eyeliner without having to re-do it several times!