I think the standard response to this would be to first foster a fun, joking and mutually enjoyable relationship with someone, then perhaps punctuate moment of making fun of them with a few touches on the arm or shoulder. Then, if the response to those seem positive, reference (even if it has to be creatively) some way something they said made fun of you, and as you say that you "get them back" with a single poke in the side ab, and gauge the reaction.
To be clear, you should be prepared for pullback or non-buy in at any point, but provided you're halfway capable of reading non-verbal queues from human beings, and you're willing to respect either signal, I've never had that approach backfire. (In other words, I've done this even with people who turned out to completely despite being tickled, and yet they still never resented or disliked me afterward, because I respected their response.)
That's about the best way as I see it to pave the way for them to reciprocate if they would otherwise want to.