Mao Sui Recommending Himself
In the Warring States Period, the State of Qin besieged the capital of the State of Zhao. Duke Pingyuan of Zhao planned to ask the ruler of the State of Chu personally for assistance. He wanted to select a capable man to go with him. A man called Mao Sui volunteered. When the negotiation between the two states was stalled because the ruler of Chu hesitated to send troops, Mao Sui approached him, brandishing a sword. At that, the ruler of Chu agreed to help Zhao against Qin.
This idiom means to recommend oneself.
例子 Example
例 1：当老师问到有没有人愿意为孤寡老人服务时，同学们各个毛遂自荐，教室里一时热闹非凡。
When the teacher asked if anyone would like to help the childless old, all the students offered to take the duty and the classroom was at once full of noise and excitement
例 2：将来说不定您会需要一位新的译员。因而在此不揣冒昧，特致函向阁下毛遂自荐，敬请原谅 。
Someday in the future you may need a new interpreter. So I take the liberty of writing you here to offer myself for a position in your corporation.
