Yap.Town

を着てたよ

was wearing

→ を
phrase Rare #27,295
was wearing 着てた is a casual contraction of 着ていた. The particle を marks the clothing being worn, and よ adds an informing or emphatic tone.
JA: 昨日、彼は青いジャケットを着てたよ。
EN: He was wearing a blue jacket yesterday.

トムはパーカーを着てたよ。

Tom was wearing a hoodie.

昨日は黒のズボンに白のＴシャツを着てたよ。

Yesterday, I was wearing black pants and a white T-shirt.

トム、白衣を着てたよ。

Tom was wearing a white lab coat.

トムはコートを着てたよ。

Tom was wearing a coat.

彼女なら赤いブラウスと黒のスカートを着てたよ。

She was wearing a red blouse and a black skirt.