I am portuguese english i not my strong xdddddd
Fiora jng is very strong if you play well(if you dont everyone will flame you, thats good motivation i think), so the kit of fiora works very good on the jungler because fiora can dive and that will help you in ganks and on steals, fiora normally as expensive items so you have to get a good farm.Fiora jng normally is understimate so use that at your favor.
Normally you will start red big guy(dont smite) then go stones(smite)(but never go chickhens because you will lose very time and life, go chickens when you buy tiamat), then after stones go wolfs go blue big guy(dont smite unless you are low health but i think with the w you are good so i never smite) then go frog(smite to have life to mini heralds).
After your frist farm go mid(depending of the wave situanion) and then try to focus their jungle to be easir to get the control of the dragon, gank bot to try to push their jungler.

Fiora needs kills to be strong and to complete their build so ks is always a solution.
W is the most important ab of fiora and you have to now when use it, dont use the combos, on my opinion use when we see that you gone get darius ult and situanions like that.
Warding is important and punishments too, do counter moves when you screw the game.

OK as you see i edit the build to give more imformation.
So with fiora jng you can push in early game (but try to solo their jungleir and not create a huge tf with 6 min of game ok), the cooldowns of fiora(-w) are not too big and this will be good on the jungle and on the fights. Mini heralds are important for vision and money.
With fiora try always chase if you have a litlle backup and never use the ult on tanks and sup, use adc or mid or feeded tops. Fiora marks are important and with fiora you can gank very, unless you are being destroyed on that situanions stay farming and smiting canon minions.
Herald is important, dragons sucks, but fight always for the frist dragon because if you do it your budys will not flame you.

So as nobody uses fiora jungler will be no difficult matchups but the champions i listed before are the ones that give me problems(Olaf at particullary). Vi is difficult too because i stones very.
Shen is good champion that helps fiora getting more important during the match if i nows how to use the tp.

For the finish thats my frist build and i do it because there is no good build to fiora jng.
I am portuguese and noob if you want advices just contact me.
My build is not so pretty like kamikaze builds but is life
IF I HELP YOU promisse that you will not be toxic in the rankeds.
Love you dudes