Chacun connaît midi à sa porte = Each one knows his own business best.
Mien
J’y ai mis du mien, mettez-y du vôtre = I have given way a bit, meet me half-way; I have done my share at it, now it’s your turn.
*Le mieux est l’ennemi du bien = Leave well alone.
Ils criaient à qui mieux mieux = Each was trying to shout louder than the other; Each tried to drown the others’ voices.
Je ne demande pas mieux = Nothing would give me greater pleasure.
Elle est mieux que sa sœur = She is prettier than her sister.
Faute de mieux = For want of something better.