To play Fiddlesticks you need Mana and Ability Power.
If you get the build like this it should be possible to kill the most of your enemys.
If it shouldn't fit this way you can run away but later more.

I use the Spells "Flash" and "Ignite". "Flash" is nice to run behind an enemy and get him this way but it's better to have it if you have to run away.
"Ignite" is usefull if the enemy runs behind the tower.

The Masteries are set like they should be best for Fiddle.

For being a strong enemy in early game you should buy Dorans Ring.
It gives AP, HP and Manaregen. Perfect for Fiddlesticks!
Then you should buy Lysandra's Torment. Its nice for farming and it hurts your enemy with magical penetration if he runs away and you can't hit him anymore.
Morellonomicon is best to be solo on a lane because with this item you havent got manaprobs anymore and you can use your your abilitys more often.
If you can't get Morellonomicon early enough you should get blue. It got the same effects.
Then Rabadons and Will of the ancients and your AP is incredible high.
Your abilitys should be unstoppable.
The shoes are your choice.

To make the most damage with Fiddlesticks you start with your R. Its best if you Dive your enemy because he can't see you setting the R and he's surprised about you standing next to him and making him damage like noone else.
In the same second you stand next to him and the crows fly around him you set him fear with your Q. He wont run away and get all the Damage your R can do.
When you set your Q continue with your W. Maybe he's so silly and attacks you but he wont have a chance.
If he runs away you wait till the W almost stops and shoot a crow afterwards with your E.
Mostly u neednt your E because they are dead before they can run away but its usefull for the early game. Hit the enemys with it on a long range!

Mostly the enemys think that Fiddlesticks is a easy breakfast to eat. But at the very latest they will know that it's not like this after you set your W on them.
The problem is his Health but i tried to conteract this problem with the Runes.
Mostly it fits this way.

Thanks for reading my guide.
It's my first one so I hope you know more about Fiddlesticks now.
Dear PikchuFighter