How do I mute someone? And will they find out I muted them?
Found it…
But this still applies…
I muted you. 
Do you see?
Nope. I hope you’ll give me another chance.
The very last one… 
Alright, I’ll be good…
Having asked the question and then marked your post ‘Found it’ as the solution, which isn’t really a solution, you need to explain your solution for those finding your thread via a search.
It was under the user’s profile, a drop down box. And no, the user doesn’t get notified.
That’s better, so now others can find the answer.