Hi, Shingeki no Silver again!
I saw you're updates, but again, your guide is nowhere near to being helpful in my opinion.
Now first to your item builds:
Simply put, Abyssal Scepter is not worth buying UNLESS you have an AP-Top or Jungle and you're up against the likes of Kayle who can poke you down in an instant. You should always go Seekers Armguard first because it's so cost efficient, giving you AP and Armor ( against AA poke ) + Zhonyas is key to get resets. Also you didn't even mention in the slightest way that you should only buy Rabandon's if you have a really big lead...in most of the cases your enemy will buy MR so you should go Zhonya's into Voidstaff, because it gives you more damage ( ADD NUMBERS! )
Now your Skill-order:
You go Q>E>W>Q>Q not Q>E>W>Q>W; I don't even see the point in going two skill points in your w pre 6.
You're 'Introduction' needs way more than just saying she's an AP-Assassine...You have to explain her role in the game. Katarina is blessed with high mobility ( Shunpo and Resets ) and AoE Burst ( Death Lotus ). Her main role in the game is to shutdown the enemy's carries before they can do their spell rotation. You should defenitly add these facts...furthermore she's tons of fun to play, because she can snowball so easily and Kat is the champ with the best set to get multikills with.
EARLY GAME:
Your main goal in the early game is to poke your enemy out of lane, giving you a gold an EXP. advantage! Try hitting the caster minions with your Q so that the last Q jump will hit the laner, then proceed to farm with your W ( BTW you don't skill it twice pre 6, because it already has a low CD ). This will guarantee to push the lane => Roam to Bot and eventually even Top if you can make sure to get a kill/tower. The main reason to roam is to get Control over the DRAGON! You also gain a lot of map pressure and that's how you can get objectives, leading into a gold lead.
ITEMS:
You don't buy Abyssal because of two reasons:
1. It doesn't scale well into late game
2. It won't give you any survivabilityif you're being focused...you will just get CC'ed

Try to explain what these items do for you in a fight! E.g.: Zhonya's will help you immensely in TFs, because it won't be too easy to focus you down, becuase of your ACTIVE.
FARMING:
Don't use Shunpo too often. If you're getting ganked with Shunpo on CD or the enemy laner engages on you, you're pretty much f*cked. You'll have to use Flash in most of the cases.
Again use Q on caster minions and W>AA to farm.
SKILL SEQUENCE > COMBO:
Poke with Q before going in, if you see an opportunity ( e.g. Your Amumu/Sona just stunned them all ) go in with your E use W then go immediately into R. Don't go in if you can't make sure to get a decent ultimate off!
PROS/CONS:
+
High mobility, therefore good roaming potential
High burst AoE Ult
No Mana
Tons of Fun
Best Snowballer in the game
LOW CD's!
-
Really hard to master
Needs a lot of decisionmaking ( roaming, engaging, etc. )
Gets focused down easily since she has to be in the middle of the fight
TEAMFIGHT:
Focus down the enemy carries, your best way to do this is a full ultimate!
Katarina synergizes well with champs who have AoE disables like Amumu, Sona, Maplhite, Blitzcrank, Sejuani etc. You should only try to engage if you can get the resets that you need, if you're being focused, use Zhonya's. In some fights it might be preferable to not use you're ult, because they will immediately try to stop you so wait for a perfect opportunity!

So now that I'm finished, I just wanted to say that you should really read my tips and use them in your guide. Also, go to TiensinoAkuma's guide and read through that sh*t, it's hella good. If you won't change you're guide to better I'll just give it a thumbs down, sorry to say that.
Bye, hope you appreciate
Shingeki no Silver!

Updated and fixed the feedback ;)

Thx for reply i try to fix it ;)

*EDIT:
If you want me to name some streamers that are exceptionally good at playing Katarina:
- TiensinoAkuma
- Bischu
- HooN ( Korean )

Hi, I'm Shingeki no Silver on MOBA-Fire and I'm here to talk about your guide!
From what you wrote in your guide I can clearly say that you have a basic understanding of Katarina, but there are a lot of things that you didn't even mention. ( I'll come to that later )
So first of all, your english is not as good as it should be, I'm sure you could have done much better if you read through it again. And basically that's the point, I'm 100% sure that you didn't re-read it. So now to the information you were giving:

( + PROS )
- You talked about her high mobility + burst damage
- Teamfight-section is okayisch

( - CONS )
- You don't explain your item build
- You don't talk about item options enough
- You could have added scenarios when to go engage a TF ( you did at least 1 scenario )

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