吹牛逼毁自己扯人蛋
[chuī niú bī huĭ zì jĭ chĕ rén dàn]
The translation for this rather informal term is roughly 'Bragging ruins yourself and affects others'. This expression is very colloquial and can sometimes have an insulting nuance, implying bragging excessively would not only ruin oneself but also affect other people negatively.