Stop cooking, Norga 
#Jayce Jungle
amber prawn
undone flax
In season 14 any champion can be a jungler. What is really important if you want to have a chance at contesting anything before level 6 is to be able to clear by 3:25 at the latest. You want to be able to contest top ganks by quick full clears and scuttle by farmers
I don't know Jayce's kit well enough to say it would work but if you can clear early enough and you can deal with invades you're pretty much all set.
rancid juniper
drop the op, curious to see the match ups and how youre doing
gentle rain
I've played Jayce JG (albeit only in norms), and I've found quite a bit of success running lethality. Ganks are not bad with ranged QE and melee QE. Clear is a little slow but if ur actually decent at the game (unlike me), it can definitely be finished at a respectable speed.
His aoe is pretty decent so he does grubs relatively well
build-wise, profane def isn't bad if you have the income to get it, but I really like youmuu's rush due to the price and stats (plus active)