look first take boots of speed to make bersekers greeves then you can take slarks favor(sell it later)then take phantom dancer(sell it later) at the end you will have
1) bersekers greeves
2)tiamat excelent for creeps
3)infinity edje
4)black cleaver
5)bloodthirister
6)and 2 bloodthirister
remember the bult depends on the enemy heroes you can always make changes to the items

i havent said anything about how to play none can learn you dont read guides just see the itmes you will learn by yourselves by playing just know that yi has big damage go jungle when you can and gank with others some times when they hunt you maybe just stay and attack if you have half health e.g especially with slarj fevor with lifesteal

if you just die often play defence and when you find weak enemy alone hunt jim also take guardian angel if die often or frozen malet to slow enemies remember not always you reach full items my often items are boots-infinity-slark-bloodthirister-black cleaver
you dont need anything more and remeber you cant kill all team just 3 at max like lux-ryze-weak hero

i take health-ignite always

shoot cleaver always maybe take randuis omen but i prefer those ones its big speed what i put but you must run alot also the health is bigger causee of warmogs ability when you kill creeps