Hic...
I may have a few of these old wives' tales mixed up (I'm not the first man to mix up old wives' tails!)
I think if you stand upside down in a bucket of water
drinking...er...a glass of water that should work.
And also jump out from behind a curtain and scare a ghost...erm or something like that.
I know a teacher who, when a child had hiccups, would wait a moment and then sternly call them forward in front of the class.
Inaviably, the child either went red or drained to white, fearful that they had done something wrong. When they got to the front the teacher would ask if the child knew why they had been called forward.
Obviously they did not.
"I just wanted to cure your hiccups for you," smiled the teacher.
It worked every time, too... or so they say!