If you are playing jungle you must pick SMITE as your first summoner spell.You will need it in the early game and in the mid-late game.In early game smite will help you clear camps faster and easier,but in the late game since you will AT LEAST have 4 completed items you will need smite to secure buffs.
I take teleport as my second summoner spell cause with Master Yi i have to farm and stack in the early game,but what if the enemy jungle ganks a lane and i will be really far from there?
I will use teleport to countergank and hopefully take a kill or an assist.If you are not sure about this and you dont have a really good map awareness then take flash,it would be easier for you.

You must follow my steps and watch my notes carefully.If you do that your Master yi gameplay will be a lot easier and you wil at least 70% chance to win games.

Here are some clips that will improve your gameplay and you will lean some trick you can do with yi. Play Video Play Video Play Video Play Video https://www.youtube.com/watch?v=vrvSMLbi4o4&list=PL_eVQGn8cLCyfprdyIKvO0Q_gy2SdUq2o Play Video Play Video

In teamfights you WILL NEVER GO FIRST.You must let the tank go in first,make sure enemies are low and then go go and kill them.

Guys if that guide helped you make sure to leave a like,it means a lot to me :D