While I'm a proponent of holding your breath to get rid of the hiccups, that's never worked for my husband.  He gets painful hiccups that never seem to go away.  The only thing that works for him is to take a huge spoonful of creamy peanut butter (NOT chunky!) and try to swallow as much of it as possible. 

He got the hiccups the night before our wedding and had to hike to a convenience store half a mile down the highway to pick up some peanut butter.  I'm glad it works for him, otherwise our little ceremony would have been punctuated by his loud hiccups.