Hey There,

my name is Philipp and Zed is my main champ. I played him a lot and this is my guide to help you with your Zed playstyle. This is only for the ones who wanna try Zed in a game and want a quick overview of his playstyle.
If you have any suggestions feel free to PM me.

Thanks and let's get into this.
Phil

Pros - energy-reliant - very mobile - strong poke - very strong splitpusher - high burst damage - Most important: FUN TO PLAY

Cons - weak early game - ult can be easily countered (Zhonya's Hourglass) - sort of item dependent - can be shut down by CC

Code:

This is the most common used summoner spell. You can use it as a gapcloser, as an intiation, as an escape. There just endless possibilities for that spell so take it.

This might be also an viable option for Zed. If you use this in combination with your ult. This will keep you enemy from running away. You can use this to escape or to catch up to an enemy.

This is a standard summoner spell in order to kill low life enemies. Zed also can use this to combo with your ult. That damage will count too.

I think these are the standard runes and masteries. This is a guide for those who want to gain fast, basic knowledge of Zed so I skip this part.

To make it short:
Zeds passive on his W increases his AD and his skill also scale very good with AD. If you like to combo and poke a lot then take Bloodthirster. If you want to 1v1 most champions and win then take Blade of the Runed King. I personally buy BT first because I think until lvl 10 it gives you more AD/hit then BotRK.

Passive: Contempt for The Weak
If the target is under 50% HP the next AA deals 8% of the opponents max HP as additional DMG. This passive can only be applied to the same target every 10 seconds.

This is a really great passive. Nobody expects such a high burst damage from one single AA and is great if you duel and you both have low HP.

Razor Shuriken:
Deals DMG to every opponent it hits.

Max this first to have a high harass and to farm if you can get in meelee range.

Living Shadow:
It is your gapcloser and it mimics all you spells (q+e). It also has a passive which increases you AD.

Skill this second because the passive is worth it.

Shadow Slash:
AOE spell which deals DMG to every target hit and it slows the enemy when the skill is casted by the shadow.

Invest 3 skill points into this skill because it gives you good AOE damage but the Living Shadow passive is better at the late game stage.

Death Mark:
Makes you intargetable for one second, which means you can avoid DMG like from Fizz ultimate. It dashes to your target and spawn a living shadoe which has the same effects as your living shadows.