My name is Alejandro, im from Argentina, im 14 years old and im on low elo.
I stopped playing ranked, so then i saw that the solo q terror is back, the feral flare.
So i dont main master yi, but i really like picking him for carrying, my main role is jungler, i play yi, jax, udyr, khazix, nocturne, shaco and lee sin.

in early game you have 2 options, if you are in low elo you will now that in some lanes there is somewho that gets snowballed, so you camp him to not lose that lane really hard and get pushed to inhib.
or you can farm you feral until you have the first 30 stacks, and then 5 more.
if a laner dies, you can ult + flash + q the enemy undertower to kill him and run away, this is really useful for giving the laner an assist and a kill for you.
but you can gank him for giving your laner a kill :)

so when you have the core build, you can gank bot over and over to help the adc get fed, or you can take a kill, and the adc take the other kill, or you can take all the kills (talk to your adc so he doesnt gets mad)
when you see 2 enemy champions group in mid, go for them (if you know u can kill them), get the double and get tower
in mid game when i have core build i get dragon always when i can for global gold for helping out the team :)
and in late game(if you had a normal early game, shaco can really troll your early jungling phase, so be careful agaisnt shaco, if u think that shaco is on you red waiting for u, call ur mid for getting a kill)you will be a destroyer of everything, every carry will pee on his pants when he sees you, so if you got early fed, dont let them reach late because they will buy GA, they will cc and maybe win the game, so if you can win the game, win it, dont dance next to the nexus. Seriously, dont

PROS: yi is a really good champion, he can carry games with a few items
really strong
really fast
good bot lane ganking
CONS: no cc
squishy
hard cc is really bad for you in teamfights

first i start with blue, wraith, wolves, wraiths, red and golems, then go b and then you can start ganking or jungling your way.

you can use Q for evading a fast damage, because is like a zhonya, example: you can dodge riven's wind slash with Q
if you think a tower is gonna give you the last shot, meditate and escape with 1 hp!
or q to a minion.
if you are low life and caitlyn is ulting you, meditate and reduce the damage.

for playing yi, i highly recommend to have a tank with good initiation, like malphite or braum.
a good wombo combo can win the teamfight, and the match.