This is a regular verb. It follows the conjugation pattern of the verb comer.
PresentPresente
Mi abuela cose vestidos para toda la familia.
My grandmother sews dresses for the whole family.
ImperfectPretérito imperfecto
Antes cosía mi propia ropa.
I used to sew my own clothes.
FutureFuturo
Esta noche coseré el botón de tu camisa.
Tonight I will sew the button on your shirt.