Welcome to the Café'. IMO as far as learning how to be funny goes, I think you just have to "have it" built in you. I am very sarcastic which usually leads to humor and I also can relate things to other things on a whim and add sum BS to it or not to make it funny depending on the situation of course. Play off of the words. The first thing that comes to mind was I just got back to town and my buddy says "hey I heard you were around". Me: " I heard you were round to! " c. And, He's a big guy plus I gained a lot of weight since we had seen each other. You could maybe watch sum Netflix stand up comedy shows, or pick up a copy of "one liners" from the library, used book store (abebooks.com is a good one) or buy a new copy. Or you can get ahold of Dave Neighbors and he can tell you every one liner ever said and you might not have to read the book. lol! :). Hope this helps.
Oh wait, there should be a local comedy/ improv club you could maybe join. I checked one out here awhile back but in CO. Check into that for sure! That is prob. The best option. You might be able to pick up on timing, body language. $.02. Jus sayin'. :). Good luck!