Originally Posted by StrawberrySiren
Take some brown eyeliner and make random dots on your face.
Funny story about that. I've once or twice confused accidental eyeliner spots with my real freckles(and I have a lot of them!)
So yeah, brown eyeliner will do the trick. Be sure to make the dots inconsistent in size and clusters; freckles aren't all the same, they're pretty random actually!