With the skills I choose and the order it tends to balance out when i start out with Shunpo you can easily last hit minions and gain gold with getting Bouncing Blade second allows you to harass the other team while still being able to Shunpo to and from combat as needed. The use of Killer Instincts is to help you to receive less damage and do more damage while harassing the other team. Finally and last we know what death lotus does spin around and around killing everything within the proximity of Kat.

This is how I use my skills.
(W-E-Q-R) I mainly do this when going into a team fight.
*When you in team fights and a person is smart enough to get out of your ult
Shunpo them and if they still are on the run Bouncing Blade them.

1) This is how I buy my items when I play cat I go "BOS"(Boots of Speed) and then TWO Health Pots to start reason behind this yes you will get hit I wont lie but if your smart enough to play Kat correctly you know you get in and get out until later in the game where your just wrecking everyones face.

2) Now why I go my SoulStealer second this can give you a great advantage over your comp. very quickly even with assists and deff. with kills, but if you find yourself getting hounded hard get your Hextech after you get your first items.

3) After you get your Hextech or SoulStealer after this get your Sorc Boots helps with your Magic Pen. and increases your chances of getting stack on your SoulStealer and staying alive with your hextech.

4) Getting your Rylais is important it helps you slow enemies in team fights and helps you get kills with your ult. This also has some nice AP and health on it as well so you will stay alive longer.

5) Finshing up your Hextech GunBlade this will add some AD to the build and more Spell vamp with some life steal by the time you get this you should be just about close finshing your stacks with your SoulStealer. this is just an all around great item for Kat.

6) If the team your facing is just as good as your team is and the fight goes on the DeathCap can turn the tides of the fight by boosting your AP through the roof.

7.by the end of the fight if you want you can get a Void Staff or a Banshee's Vail reasons to get the Banshee's Veil even early game is to stop people that can stun you in your channeled ult. Bow the reason to get a Void Staff is to to basically put your enemies into the ground with Magic Pen.