The clothes you wore at the concert last week were cute.
The outfit you had on at the concert last week really suited you.
この場合、次のような言い方ができますよ。
ーThe clothes you wore at the concert last week were cute.
「先週のコンサートであなたが着ていた洋服は可愛かった」
ーThe outfit you had on at the concert last week really suited you.
「先週のコンサートであなたが着ていた服はあなたにすごく似合っていた」
ご参考まで!