what do you say instead of cursing?

Question

there are certain situations where i try not to curse. example: i will not swear around small children, i just wont. even if their parents do, i try my very hardest not to. instead i say things in other languages that no one knows are swears, or things like "oh my giddy aunt"....usually things exclaimed by british people. if you dont swear, what do you say instead?