EASY! At the begining of game you only should so level and earn money!, you kill creeps and when your creeps are in their tower go jungle!! but the most important isdo lvl and earn money all time!!
when you have level 11 and have got Youmuu's Ghostblade, you can fight with any champion!! only you should use your ULTIMATE WITH THE ACTIVATION OF YOUMUU'S GHOSTBLADE... and YOU ARE INMORTAL... you should remember use your stun and your shield too! if the other champion run.. you use Ghost and stun, when you are 1 vs 2/3 use exhaust and stun... really you are inmortal!!

The first object you should buy is AVARICE BLADE, with this object u have critical strike and money, then you buy BERSERKER'S GREAVES, then you buy ZEAL, with this object you have more critical strike, attack speed and movement speed, then you buy THE BRUTALIZER, with this object and avarize blade you make YOUMUU'S GHOSTBLADE, the principal object!!! then you buy INFINITE EDGE and with the zeal you buy PHANTON DANCER, in this moment all your hits are critical... is time to buy life, for this reason you should buy FROZEN MALLET, and your last object is THE BLOODTHISRSTER, the object with more ad in the game!!