。
My mother made new clothes.
Literal
Mother [topic-は] new clothes [object-を] made
A plain-form statement using 作る ('to make') in the past — 作った. 服 is the all-purpose word for clothes (Western or otherwise); the more specific 着物 narrows to traditional Japanese garments. 母 is the standard humble term for one's own mother in formal/written contexts; the warmer お母さん is more typical in casual speech.