You'd think if you're a writer- making up things would be easy. Oh that doesn't apply to the spoken word. I can't lie to save my life. Off on a side track here - well I'm a writer!!! - I once took my kids to the cinema for a 12 plus movie. Can't remember what it was - the oldest was okay but the younger was 10. Bad mother. Yes, I know but he pleaded. So I practised his new birthdate in case I was asked. Got him to practice how old he was. Got to the kiosk to pay and the woman said - is he 12? No, says I. Son kicks me hard. Realized my mistake and I said he's 13. It was a miracle we got in.
Back to the topic - I need to make up some cuss words for an alien and its much harder than I thought. I've spent too long on Google looking for ideas though the suggestion to make up words starting with f, c, t and sh is a good one. But how do you stop yourself falling into the trap of sounding stupid. The words won't sound like swear words to people that read it but if the character is an alien - how can you have him say - well you know the words.
So far I have - Legolian Hell, zimboots, zimpra s..t and it all sounds a bit childish. Back to Google.