Rub ice along your chest and drink cold water. The chill will stop you diaphragm from spasming, which is the cause of hiccups.
I read somewhere that they suspect that the reason we get hiccups is because of some teeny tiny part of our brain that is a remnant of when we were fish type monsters without the ability to breathe air, and the spasp is that part of us panicing because it thinks we are land drowing. Which falls in line with the diaphragm spasm activity.
The last time I had the hiccups was when I was maybe ten, possibly eleven.
Which was fifteen or sixteen years ago depending on which is correct.
I don't remember what they feel like, and don't expect to ever get them again.