Most Helpful Girl
Are you talking liquid eyeliner on your upper lash-line, or pencil liner? Either way, I found the best way to prevent smudging is to invest in high quality liner that is a bit more expensive but totally worth it.
One that I swear by, has been raved about as the best by celebrity make-up artists and isn't all that much more than drug-store brands is liquid liner by Stila. Their pencil ones have a lot of staying power as well, to the point that I'll put some on before a night out clubbing where I get all sweaty, rub my eyes a couple of times and everything is still in place when I get home a few hours later.