At level 1, try to farm and try avoid your opponent. When there are only 3 minions left, use your Q so you hit the creeps and your opponent. Mastering this trick will ensure lane dominance. When you hit Lvl 6, you can roam to different lanes to help them or get some kills, help top lane more if bot is alright and top has a late game carry such as kha zix etc. If bot needs help against a late game carry like vayne, gank bot. But before you go to gank a lane, ask your jungler to hold your lane. Also ask your jungler for blue buff because Master Yi is mana hungry.

When in mid game. Try to stick with your teammates to avoid feeding and go in teamfights to win. Winning teamfights is 1 step closer to Victory. When your team is alright without you then go backdoor to brake there turrets to help your team. If you get ganked when you are doing backdoor, use highlaner and ghost to run escape quickly before they catch you. Mid game is all about taking turrets and winning teamfights.

In late game, this is when you get powerful and destroy the enemy in teamfights. When you are in Mid and they engage, Use Highlander immediately and use use Alpha Strike on the closest enemy champion. When Alpha Strike is finished, Use Meitate or use zhonyas hourglass to wait for your Alpha Strike to come back. Then Alpha Strike again and use auto-attacks when your abilities are on cooldown. When you win the teamfight you can either get Baron Nashor with your team or push to win. I recommend to go for baron instead, because the enemy team might counter your push and lead to a loss. Whenever your blue buff is up, take it. Its crucial to your survival. This was my Ap Yi guide, Use it and you will be successful and will be called OP.