My build consists of the damage that you need and the items you need to be a tad bit tanky and be able to sustain.

I use Physical Damage runes so that I can do a lot of damage at the start of the game and get an early lead and I use Armor runes because I am mainly going bot lane, I also use the mana regen so I can almost constantly poke the enemies and farm in my lane.

I go with more of a Offensive mastery page and a small amount of resists, so that I can outplay and sustain enemies in whatever lane I am in.

I get Boots Of Swiftness which some people don't like because Ezreal tends to be a slow moving champion but with Boots Of Swiftness and Trinity Force you run at 437 which allows you to out run most players and allows you to chase enemies.

I get Trinity Force because the built in Sheen doubles your damage and is just insane in combo with Mystic Shot, I also like it for the health and slow on the Phage which also is nice in combo with Mystic Shot, I also enjoy being able to occasionally crit and moving at great speeds.

I get Blood Thirster as my 3rd item because of the lifesteal and the attack damage.

I get Last Whisper because most enemies build armor to shut the A.D Carries down and I get it even if you don't build armor because it makes your attacks act like true damage.

I get Wit's End because it gives the Magic Resist which is always a must and the attack speed and additional Magic Damage.

And last of all I get Madred's BloodRazor for the attack speed, armor, damage, and the shred capability.

I max Mystic Shot first so I can poke for a lot of damage and then when I get sheen which is around level 4-7 for me I can do around 250-320 damage to people I am against in my lane.

I max Arcane Shift second because I like to get up to people when they are alone to get the quick burst off with Arcane Shift and my Mystic Shot.

I max Essence Flux last because the only real reason I use it is to get my sheen proc off on turrets or to give my fellow teammates attack speed.

And of course you max TrueShot Barrage by level 16 it is a must.

I use Exaust so that in a fight if its me against two other people I can immediately shut somebody down and burst them till they are dead and then kite the other person around and I use Ignite to fight somebody with a lot of life steal or pick up the kill if they are getting away from me.

This build is mainly for the caster Ezreal players that that like to use their skills more than going crit, it also has a lot of sustain to it.

You can use your Mystic Farm to farm almost as much as you like because you have a lot of mana regen.