Nouns ending in -ier are usually masculine.
Is métier masculine or feminine?
lemétier
The rule behind it
95.4% of -ier nouns are masculine
In context
Mon métier et mon art, c'est vivre.
Living is my profession and my art.
Chacun à son métier doit toujours s'attacher.
Everyone should always attach oneself to one's trade.
Elle lui a enseigné les ficelles du métier.
She taught him the tricks of the trade.