keep (your) nose clean

to avoid getting into trouble or doing anything illegal.

I'd only been out of prison three months so I was trying to keep my nose clean.

• Keep shirt on!
• keep someone at arm's length
• keep someone at bay
• keep someone company
• keep someone down
• keep someone guessing
• keep someone in check
• keep someone in mind
• keep someone in the dark
• keep someone in the picture
• keep someone on a short leash
• keep someone on a tight leash
• keep someone on the edge of seat
• keep someone on the edge of their seat
• keep someone on their toes
• keep someone on toes
• keep someone posted
• keep someone sweet
• keep someone up
• keep someone up to date
• keep something at arm's length
• keep something at bay
• keep something dark
• keep something down
• keep something from