Not Updated For Current Season
For the runes I use attack speed... I use to use att dmg but his Q isnt really a damage spell, its more of a chase spell, so I use attack speed cause of passive, so if im in a 1vs1 situation I get my passive heal faster.
For masteries I go for standard attack and utilities masteries, utilites masteries might seem strange but I think the experience boost really gives you level 6 faster so you can gank more often and get feeded fast.
I start of with vampiric scepter, so I can stay in lane until I get 1650 gold for my BF sword, after that I rush for the bloodthirster and boots and farm a bit so I get my BT stacks up to max 40dmg. After that I go with the standard critical items, phantom and infinity, I start it with zeal cause of the movement speed for chasing. After that I get my secound phantom so i get a lot of critical chance. The last item depends on the opponent team, i usually buy another bloodthirster or black cleaver, but you can also buy banshee if your playing versus a nuke AP like veigar or leblanc...