First day, new job...

[TheLasrStraw]

...in a school will be an Inset day so staff will be in casual wear.

But I want to make an impression, so what to do?

Have you checked it is casual wear for inset? Some schools insist on business dress even for inset days!

I’d just fit in with casual wear. Not scruffy though.

Just opt for smart casual but nothing to short or low
Good luck in your new job!

Something bright! It's memorable, & I'm so bored of looking at people dressed all in dark (black / grey).