My newborn also always hiCcup. ESP when I put her to bed without burping her enough. InitiAlly see already very heart pain. But I read before that it's normal for babies so small to hiccup cos their passage wAy not developed yet.
Normally when my baby hiccup I will latch her on to let her suckle awhile. It will stop after a few suckle. If not I will pat her back for awhile it does the trick too.