I did a video several years ago on how to do it, but it was definitely time to do a new one.
This is a simple way to create a winged eyeliner with just two products:
MAC Flat Angled Brush 263
(I prefer this brush, however, I do have an Eco Tools flat angled brush I love as well.)
SmashBox Gel Eyeliner Black
(I also use Maybelline Eye Studio Lasting Liner and MAC Fluidline Eyeliners)
This is how I do it: