Does anyone have any tips/suggestions for supporting for jhin? I feel like I have the worst time with Jhin. I feel like my lanes get shoved up too far and I cant secure kills with him. I just don't know what he from the support.
It depends. Could you tell me what Champions you play?
I'm a Jhin main myself, so I think I could give you some answers. :D
You don't.
You sit back and collect your freelo from this bullshit overtuned champion.
ONE RULE:
NO 
EVERY support works GREAT! (at least, for lane XD)
Jhin likes a CC engage he can chain his CC on. He likes damage he can chain his CC on. He especially likes damage that gets targets low and lets him proc executes on. He likes healing that lets him profit even more from aggressive trades. Everything's good with him.
Lategame you might actually need the right kind of CC / shield / heal to protect your ADC. Let that influence your choice too.
His absolute best synergy is Morgana, she does the CC, and big damage (her damage is boosted when you root people in her puddle) and being able to puddle and use Jhin's captive audience through minions lets her set up easier Qs or Rs.
If your Jhins are autopushing, you need to reset the minion wave by crashing it into tower or letting the enemy lane push...and BACK OFF if someone's coming to gank. Jhin players autopush if they rely on Q to farm with. A good Jhin might autopush if he's hitting Q harass.
So for you- BAM! Morgana. Perfect synergy and you can use her damage to reset the wave if you need to- or harass under tower if you want to (Remember Jhin can kill under tower, easily) E to save whoever's most caught out if jungler comes a lookin'.
You don't, you just sit back and enjoy the carry from this bullshit champ.
Land picks with your CC that he can follow up with his W. Pretty much the biggest offensive thing.
one cool tip when with a jhin is if he has his forth shot up you can be a little aggressive because once jhin has forth shot no one want to take that damage so play up be aggressive and deny CS
Well I play Pyke personally, and I like to hook (but not all in) the enemies when Jhin has his fourth shot up or coming up. In terms of mage supports I'd just think poke them down with him until you can land some kind of CC then he roots them and y'all kill them.
You need a champ with some sort of AoE damage and at least one skill for peeling.
AoE basic abilities allow Jhin to proc his W root more effectively. Good examples of this are Morgana, Zyra, Soraka, Brand, Vel'Koz, Fiddlesticks, and Lux.
Peel abilities are pretty obvious. All champs listed above have some sort of peel, but the better examples are Morgana and Zyra, as their peel/zone is a bit more reliable. Also, in this department, champions like Leona, Taric, Thresh, and Braum work very well. They can even allow Jhin to follow-up initiation with a stun/slow/hook into a Jhin root.
Laning: try to setup poke for his W proc. Zone the enemy laners into bad pathing patterns so as to make Jhin's W easier to hit. Also try to use Jhin's traps to zone the enemy laners into choosing either to hit his traps or take your harass. When Jhin ults, you have to make a snap decision: locate the jungler on the map. If you can't see him, stick closer to Jhin as his ult locks him into place. If you can see the jungler, assess how quickly he can react. If their jungler is far away, push up on the targets Jhin is aiming at, trying to hit them with any sort of CC you possibly can.
Teamfighting: look for picks. Try to layer some sort of damage onto enemy champs that are out of position and/or squishy so Jhin can possibly hit a W root on them. Try to stick close enough to Jhin that you can respond to a dive effectively. If you're playing a tank support, save your best peel for when Jhin is getting dove. A good rule of thumb is to be in range for Knight's Vow to transfer damage onto you (if playing a tank support). Or you should play close enough where you could cast a shield or pop Locket on Jhin to give you time to close the gap. When Jhin ults, it's the same as before, except your job as support is to stay close to Jhin to peel anyone that sneaks through your front line to kill him. The exception to this is if you're cleaning up the fight - then you should just push onto the enemy to pressure their escape.
Itemization: do not build Ardent, even if you're playing an Ardent support, unless it helps another member of your team (i.e. Kindred, mid Corki, Master Yi, etc). Jhin doesn't scale well enough from the attack speed buff to make the Ardent a good buy if Jhin is the sole auto-attacker on the team. You're better off getting Locket and Redemption, as keeping Jhin alive through his reload and during his ult channel is far more important.
Your main objective is to keep his immobile ass alive. Sure, recently Hail of Blades and Stormrazor have made Jhin a beast, but these tips were relevant before these issues, and will be relevant after these issues. There are more finer touches to support, but those touches are pretty universal to support as a role, and aren't really Jhin-specific.
Hope that helps.
zillian/leo/braum/(attempting to learn nami)
Jhin excels at being a lane bully. You should try to play up with him as his primary way of getting ahead in lane is to aggressively poke and zone with his fourth shot. As the support, you should be trying to trade with him to help facilitate this. All in Supports such as morgana, thresh, and alistar work well with him as their CC can be used to chain his CC.
Moral of the story is be aggressive in laning and stick to his ass in teamfights because he's squishy and can get preyed on by Assassins.
