LOL, you have the opposite problem of me, I want to make my eyes look longer. Anywhoo/... you could try lining your bottom waterline in white and then layer mascara on your lower lashes so its more of a doll like roundness. and when you don't like the waterline in blac kit makes your eye look rounder because your not closing in your shape. Also for the top lid do concentrate and line the middle part of your eye and thin it out on the edges (the opp of waht you want to do when u want to make your eyes appear longer) howevver don't overdo it as you don't want it to be obvious. Do curl your lashes and apply mascara, concentrating on your middle lashes and less on the outsides.
I also find that walking around like ur very surprised helps (joking)