avec simplicité et bonne humeur

[scloughley]

Tout le monde met "la main à la pâte" ... avec simplicité et bonne humeur !

Hi there, I'm struggling for le mot juste for the latter part: "everyone pitches in, at ease and in good spirits"?
I know exactly what the sense of it is, but I simply cannot find the right words. Even these don't sound quite right

Anyone care to help me find the right idiomatic equivalent, since an exact translation will probably not be correct?
NOTE: This is a phrase from France, rather than from Québec or other francophone lands (if that matters).

 

[Kelly B]

Cheerfully and with no fuss?
I've reversed the order because the negation would sound weird if it came first.

 

[scloughley]

Thank you. I like "cheerfully" - that seems perfect.
"with no fuss"??....hmmmmm.....not so sure but probably as good as "at ease"?
Anyone else care to weigh in?

 

[Itisi]

'in an informal, light-hearted manner' ?
'informally and light-heartedly' ?