Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
As Kennen you will most likely end up soloing a lot. Kennen can outrun and survive anything unless he becomes CC'd, you will need to move at all times in order to prevent this from happening, if bad comes to worse, MC boots and flash will hopefully save the day.
Always start with Thundering shuriken and max it out first, it is your main harassing and damaging ability which will turn the outcomes of many fights by you building up charges and then harassing further with electrical surge which will bring your enemies down to 50% ish before they start deciding wheter to port back or stay - if they do stay, you will most likely get a fast kill.