Getting Ancient coin and refillable potion at start is a must, stand a little bit ahead of your adc and q the other team away from minions, bandit mastery helps with giving you poking money and minions dying by you money. Make sure to dodge their attacks, and when they slowly push you back far enough your adc can unleash upon them a bit. Make sure your adc gets as much minion farm with this. Heal jgl if they are very close as well
Health regen is a must for seals, as healing takes part (10%) of your health, and you want to stay in lane as long as possible. Magic penetration goes with her q's life regen, so that is important, but armor marks might be more beneficial depending how you play her. Ability power is kind of important, but there are more important things as well.
Greenfather gift or bandit is very helpful, as you can pop out of botlane bushes even if it is warded and hit other team with a q taking away 3% of their health too, but bandit might be better as you aren't cs'ing minions, and constant poking both help it. Dangourous game may be a better one especially if you have a really good top/mid/jgler as your ult can give you assists. Windspeaker's blessing is definitely the keystone to go with, her w has a very short cooldown and who can say no to some extra 10% heal and armor to your ally? Note that your ult gives them this buff too
Ardent censor is a core item, as spamming w is very helpful especially with high AS adc's like jinx, because of the passive on it. It can help almost any champion, all of it's passives and such are helpful in many ways. Talisman's active and passive are super helpful, giving you both regen and a safe way for you and your allies to get away, very good regeneration ways and armor. Boots can go many diffrent ways, but typically magic treads or ninja tabi is the best ones to go with. Rylias crystal scepter slows them, plus more health and AP for you. Zhonyas hourglass's active can be just the thing to save you from a karthrus ult, or when you get baited into the middle of a trap with some friends. Become untargetable and save your surviver allies
Your team will always be at full health if you are both by each other, and they can just sit being full-out attacked by about 4 tops other team champs, and end up fine. Your e and q is awesome for this