Inhale and Swallow Technique
Inhale through your mouth as much as you can. Then, swallow your saliva without letting any air go out. Inhale through the mouth again and swallow again, not letting any air slip. Do this as many times as you can. It may get tough and tougher but do not stop. You will reach a moment when you will feel that you cannot swallow the saliva anymore. Try once to do it the last time. When you are sure that you cannot go ahead absolutely, release the air through your nose. This resets your breathing.
Exhale All But Little
For this one, inhale as much as you can and a little more. Hold it. Then exhale slowly almost all the air while holding some. Repeat this as many times as it takes to stop the hiccups. They usually stop within 20 to 30 seconds.
The Diaphragm Technique
Inhale a deep breath and hold it. After you have done that, close your mouth and plug your ears (could be with your hands). Now, move your diaphragm up and down while it moves when you are breathing in and out rapidly. You can exhale when your hiccups disappear or when you cannot go ahead. If you still have the diaphragm spasms on, try again.