Translation of a phrase

Salvete,

I’m trying to translate the following phrase into Latin: “Don’t work too hard” (ironically I’m working very hard to try and translate it…) I took Latin for many years, grade school- undergraduate, but have grown very rusty.
I’m having some issues, here’s what I have so far:
Noli arduum nimium laborare

Would “too hard” be in the accusative?
Is “noli laborare” right? Or would you use the imperative or "laborare?

Gratias vobis ago!

“Don’t work” can be translated either nōlī labōrāre (literally “do not want to toil”), nōlītō labōrāre (“want not to toil”) or nē labōrāueris (with conjunctive perfect). Latin labōrāre has the connotation “to labour, to toil”, but this may well be what you are after.

“Too hard” could be translated with an adverb phrase nimis grauiter.

Thank you!
I wasn’t sure, I like like that it can be translated “to toil” but would operor be more colloquial?