If you were to describe your mood with a colour, what colour would you be?
If you were to attach a colour to your mood, what colour would you choose?
ーIf you were to describe your mood with a colour, what colour would you be?
「あなたの気分を色で言うと何色ですか？」
describe one's mood with a colour で「気分を色で言う・描写する」
ーIf you were to attach a colour to your mood, what colour would you choose?
「あなたの気分に色を付けるなら何色を選びますか？」
attach a colour to your mood で「あなたの気分に色を付ける」
choose で「選ぶ」
ご参考まで！
カナダ 
