what are you building ? Here's what I do, Ive got mastery 7 on kayn already, Jungle, dont worry about ganks right away. Farm really hard about the first 10 minutes, maybe drop off 1 quick gank or so to try an scare out a flash. Get your warrior enchant finished and get to level 6 maybe 7. then you pick a melee target and work with your laner, go in heavy get the kill with your ult. for transformation, then you go back to farming for a bit til you have finished boots and deaths dance. Then you can just camp bot lane, that should net you a double kill pretty easily if you land your knockup and use ult well.