Answer:
there are alot of answers but these are the fastest and best ways i know
use the bathroom
it won't always work but it usually does, and if it doesnt, see if you have a fever or need to vomit
stretch
i know this sounds weird but just sit down and do stretches that you would normally do in the morning when you wake up just make your muscles tense for a second and when you stop your stomach will probably feel better
eat mint
this works if you have a mint plant or just some altoids or something but dont eat too many as this will make your stomach feel worse if you have heartburn DONT swallow it, and dont swallow the mint leaf at all
drink ginger ale
this will only work if you have a stomach ach due to acid in your stomach with nothing to do because it calms the acid bubbles
eat
i know this is probably the last thing you want to do when you have a stomach ache, but if your stomach is making noise, then it probably means you/'re so hungry it hurts, so eat something (REAL food, not cookies or candy or cake or anything) i would suggest bread for this because if it doesn't work, it will go through your system quickly.
entertain yourself
the most common stomach ache isn't actually a stomach ache at all. its a mental stomach ache, lik on the first day of school, you think your stomach hurts but it really doesn't you just want to think that so that you can stay home from school one more day. just watch tv, go on the computer, read, or do something else it usually helps.
NOTE: If your stomach ache stays longer than a day or if you have a headache with it for longer than a day, then go see your doctor because these can be signs of rare but extremely serious diseases or appendicitis.
Also TRY A PEPPERMINT!!! It works for me everytime. It'll calm your stomach.