Even though you might think some clothes look cute, they often don't look that good on you.
ーEven though you might think some clothes look cute, they often don't look that good on you.
「洋服を可愛いと思っても、その服が似合わないことがよくある」
to look cute で「可愛く見える」
often で「よく・しばしば」
don't look that good on ... で「…に似合わない」
ご参考まで!