No one knows how to play Jacks not even Phil Ivey or maybe he does.
https://www.youtube.com/watch?v=JGINuq5UaD0
People play Jacks too aggressively or too passively getting the balance right is an art. Jacks is a hand to go all-in pre-flop with when you are less than 10BB and up to 15BB in tourneys, stacking off with more than 30BB is a mistake unless you have a good read!
I advise playing Jacks in early levels as a set mining hand as you will generally win a small pot or lose a big one, when the antes kick in start 3 betting them.
This video tells you all you need to know