You can't. Only one thing you can do and that is try to trade when they go for the shove, sidestep their q and trade autos lvl 1. If they hit the q u lose the trade, if u dodge q and trade autos you either trade evenly or slightly win the trade if you get out before his q is off cool down, but the important thing is that it slows down his push more than winning a trade. Then level 2 you repeat this AFTER he uses his 3rd tornado q, and if you dodge q again you just win the all in. Remember to save your E for auto-e-auto cancel, it can turn the close level 2 fight and burst from around 200 hp pretty quickly with conq stacked. Kat level 1 is weak but against most mid lane melee champs it's enough to contest the first wave if you start dorans blade and have conq. Her lvl 1 into ranged champs is what sucks.