Jinx is bad against mobile junglers such as Lee sin, Kha'zix or Xin'zhao. Jinx clears fast after lvl. 3 so you wont fall behind in farms. At least not too much. Also in your kit there is root and slow for getting away if a tough sitsuations. I also suggest not to pick jinx if your lanes can't get any prio as you are voulnerable against roams and counter farming. You also don't have good way to solo objektives wich can loose you the game.

Remember! This build is off meta and I do not suggest running this in your ranked games.

At the start of the game you start preferrably red side and clear red -> raptors -> wolves -> blue -> Gromp. (Remember that your regular autoattacks deal better dps in single target camps. Secondary weapon on the other hand is better against wolves and raptors .You also can use secondary weapons AOE autoattacks much more than you could in bot lane.) I do not suggest going for krugs in first clear because you take a lot of damage from them. I also don't suggest going blue buff to gromp as your first two camps becouse you clear quiker multiple target camps and take less damage from them. First clear your smite is important as the clear isn't very healthy. I usually smite second camp and fourth one when starting from red.

Ganks
Your ganks are not bad. Jinx W slows enemies wich gives you and your laner a good change to run at them and kill the enemy. Also your Ultimate rocket can make a difference in a fight on the other side of the rift.
Dragons
Jinx cant solo dragons or heralds well in early game and I suggest you to ask for help from laners ahead. If laners are not ahead, rather than going solo for the objektives, try and help lanes so that they can help you.