pros

-good escape
-long range and good auto attack dmg
-good finisher
-hard to gank

cons

-squishy
-easy to kill when playing as melee
-easy to catch ult

take a long first for good dmg to get up your cs fast.

vampiric for life steal for more survivability will help

then rush for berserker for atk speed and blood for high dmg + life steal

once you got the bloodthirster get phantom for critical movement and great atk speed

then take frozen for slow and anti-squishy

black cleaver will give u more penetration on the tank and enemys

last but srsly not least the infinity for high dmg and great crit chance + dmg

take flash + ignite for more chance to chase escape etc...
and for finishing off your opponent


take peacemaker first for the dmg and your trap for dmg+stun
your 90 caliber net is mostly used for escape or for chasing
like allways lvl up your ult when possible cuz it does nice dmg =)

just the normal utility for recal mana-regen etc...
and the normal atk speed penetration for better dmg

take atk dmg or armor penetration mark to get good cs and do good dmg
armor seals will help u to survive more atks from the other adc
scaling magic resist will help you for late game team fights
and the atk dmg quintence also for some more dmg