Have/with your nose in the air
Have a snobbish or disdainful attitude
- She walked past me with her nose in the air.
Have a nose for
To have natural ability at something
- As a reporter, he had a nose for a good story.
It’s no skin off my (your) nose (back)
The outcome will not affect me personally
- It's no skin off my nose if you don't take my advice.
Keep your nose clean
Avoid trouble or situations that compromise one’s honesty
- I'd only been out of prison three months, so I was trying to keep my nose clean.
Keeping one’s nose to the grindstone
Working hard on something repetitive or tedious
- She kept her nose to the grindstone all year and got the exam results she wanted.
On the nose
Precisely, at an exact time
- Her description of the play was right on the nose.
Powder one’s nose
To use the restroom (lavatory)
- Would you get me another drink while I go and powder my nose?
Right under (one’s) nose
In an obvious location, yet overlooked
- I spent all morning looking for the book, and it was right under my nose the whole time.
Stick your nose into something
Intrude into something that is not your affair
- You’re always sticking your nose into my business.