1. Focus on critical thinking skills.
Here's some books that sound good. I've never had a chance to read them.
If they start talking about the teachings, couch them as things "some people believe" and that beliefs are choices. Ask them if they know what other people believe and discuss. How would we know which god is real, jehoopla or Thor? They are equally as plausible and have the same amount of evidence.
Maybe you could have informal little conversations ready to use when you have an opportunity. For example, there is ample evidence no global flood ever took place, there was no such thing as the water canopy, etc. (Probably one of the jw teachings most easy to disprove.) Discuss all the flood myths that predate the bible.
2. Show them how to be a good person outside the borg. Take them to volunteering events, etc.
3. Show them you can have good, wholesome fun outside the borg.
4. Read the bible together. Read a very small snippet and let them discuss it openly. The bible is a totally evil book and has a lot of mistakes a creator wouldn't say about his creation (bats are birds, Earth is a circle). Stimulate and permit open examination of these things. Gawd sent His Super Special People into battle several times knowing they'd all die. Why would he bother wiping out the population with a flood himself and later not be in the mood for swimming, so he needs people to engage in combat for him? Why did he say to dash babies against rocks?