This is the build i have been going with some matches and i find it realy good. It makes you able to do huge amout of crits and still be able to take some hits from the enemies. The reason why you would want a bit of cooldown reduction is that your Tumble is realy important and has a 2sec cooldown with none CDR. You want to get the blue buff realy often to be able to stay in the fights for a long time.

Pros: Good 1v1
Good chasing
Good escape
Great Dmg
Cons: Need walls to stun
Not a good farmer
Can be denied easily if u dont deny good enough ur self.

I got with 9 Marks of desolation couse it's pretty much good on all the AD champs.
9 greater seal of Evasion couse when u dodge u get more movement speed couse of one of the talents.
9 glyph of focus for some CDR
3 Quintence of Desolation for Armor pen or Swiftness for the extra movement speed, if u get boots of switness there is no point to get Quintensess for the speed.

The items are picked by how i think is good. Tho feel free to come with suggestions. all i have to say about them is Bloodthirster = Good Lifesteal and good dmg. Trinity force is movement speed and the extra dmg after using a spell with will make u crit 700 with Tumple+ auto atck with only blood thirster and that one. Infinity edge for dmg and crit dmg. And least the Guardian angel to make sure they dont ace your godlike =D

I choose Flash/Ghost couse i like playing agresive with this champion and people do never manage to run away from you. The flash is good couse u cant roll trought walls so flash is the only jump trought wall mechanism u got.

Other good spells is
Heal: It often keeps you alive 1v1
Teleport: Its good if u wanna keep pushing your lane.

Dont ever use:
Revive, its just ********.
Fortify, Leave it to the tanks/supports
Smite, This aint a jungle guide...
Clarity, its a waste on this one.

Deny your enemy=win in mid lane. Get blue buff. Dont give up a chase unless you are running into a trap. Try to kill mid at level 6 or earlier. Gank alot couse u will get quite fed easily then. Dont belevive them when they say they got cake, ITS A LIE!