stand on ceremony
US /stænd ɑn ˈser.əˌmoʊ.ni/
UK /stænd ɑn ˈser.əˌmoʊ.ni/

1.
andarse con ceremonias, ser formal
to behave in a formal way, or to insist on formal behavior from others, especially when it is not necessary or appropriate
:
•
Please don't stand on ceremony; just make yourself at home.
Por favor, no te andes con ceremonias; siéntete como en casa.
•
There's no need to stand on ceremony with old friends.
No hay necesidad de andarse con ceremonias con viejos amigos.