This is my first guide ever so plz don't flame rather say positive critics how to improve(most of people appreciate it)
Anyways about fizz:he is melee assassin(fighter)that excel at bursting priority targets,you'll have to train him cuz he is tough to master but OP when mastered.

So about ranked,people are going to counter you,and in low elo people most of the time will just fail at that but still be carefull don't get too cocky,wait for their mana pool to deplete or when their damage spells are on cd.I don't know how to play with him at higher elo cuz im only silver 1 :( but that doesn't mean im noob,all I know that people on high elos will handle you and you are going to be compelled to go roaming and thats good cuz you will help other lanes and you are going to be able to not fall to much behind against enemies mid btw it's best for you to start roaming at lvl 6 or higher.

pros:VERY VERY high damage
can carry easily if played right
if playing him tanky you are going to be able to make damage to their team before going down and that way your team wins
fun to play
great abillity to roam

cons:melee
hard to master
needs cs or kills

teamwork as always it's most important thing in this game,with fizz you must immediately jump on adc or apc and burst them thats your primary job,if one of them is dead your job is almost done,if you manage to survive just try burst target that deal most damage,or the ones with low hp,when your team goes in try to flank the enemies cuz thats the easiest way to assassinate.

farming with fizz is most of the time hard,cuz when you get in melee range to last hit you are opened to poke so if you already have hard job farming lvl up e instead of w...thats going to make farming more easily