Thank you for the replies, everyone.
KaliMa, I probably should have mentioned that I'm not a good winker. For the past few days, I have been in the habit of adding, "just kidding" ...especially if people start taking me seriously. Hopefully, that will work out in the future. Any more tips would be helpful.
Pobodys_Nerfect, I also considered this recently, but it feels awkward to me. I'd like to have a smoother transition than just a laugh and then start a new topic. How can I pull that off? Are people taking my bad jokes too personally? I don't want to "attack" people's egos; should I stop altogether?
millie, the same thing occasionally happens with me -- missing sarcasm. It used to more often. I've learned how to better pick up "tones," or just pitches, like stressed words, or phrases that clearly aren't true. I'm probably just used to it by now, but it requires a good ear in order to pick up the habit. It took me long enough to learn puns, but now I use them every day. Just an eye roll (which is sometimes what I try doing, along with my new "just kidding" phrase) indicates sarcasm.
I have mistaken people's sarcasm as truth before, lots of times. When I asked someone, "How's the traffic doing now?" and he responded with something like, "Great," I believed him, reacting positively and relieved. That's when he told me it was really bad. I should have guessed that he was joking because I had problems in traffic earlier that day, which was actually the reason I had asked him for the update. This sort of thing -- asking for simple updates and getting sarcastic responses -- happens often for me.