I would say practice. You can't be afraid of failure. I say the first thing that pops in my mind and I believe my success rate has steadily increased. Or maybe I have just offended mostly everyone that doesn't have the same sense of humor as me, therefore increasing the chance that I am surrounded by slow witted people who find me funny. Hmmm, will need to give this some thought....
I have no idea... maybe there are some games that sharpen one's ability to think abstractly and on the fly, since that seems to be the essence of wit - thinking of the thing other people didn't think of and saying it before anyone else can, in a way that makes people laugh. Given that I'd say it seems to be a quality native to Ne, but an ENTJ I know is one of the wittiest people I know, and Carebear can be very witty too at times... though I guess INFP's do have Ne secondary... Many of the things I say that people call witty leave me standing in bewilderment cos I didn't really mean it to be - I was just almost compulsively voicing something I observed in whatever words came to me first... I don't realize it's funny until I hear them laugh and look at it from their POV.
I'll have a think about it and see if I can think of any situations or environments that I've found to help hone/encourage that kind of thinking... I think whatever they are, they all require a person to be able to not take themselves too seriously... well, all people present in the situation.
Do you mean the rapid fire sorta wit, in fast-paced face to face interactions or forum threads? Or the ability to come up with a wickedly dry and rapier-sharp comment on a forum, where you have time to think about it?
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