He attended Ng Wah Catholic Secondary School and the Hong Kong Baptist University College of International Education.

Lau participated in a musical class hosted by RTHK and performed as a busker[1] for several years before transitioning to work as an entertainment reporter.

In 2018, Lau quit his reporting job to audition for ViuTV's reality talent competition Good Night Show - King Maker, and finished in top 20.

While only the top 10 finalists were guaranteed a contract with ViuTV, Jer managed to catch the attention of producer Ahfa Wong, who invited him to join the boy group Mirror.

[3] Lau's debut single, the soft rock ballad "Tale of Water Torture" (Chinese: 水刑物語) was released on 29 February 2020.

Lau again collaborated with singer-songwriter Ng Lam Fung and lyricist Siu Hak on his fourth solo single "A Madman's Diary" (狂人日記) released 17 March 2021.

Lau remarked that "A Madman's Diary" is a tribute to legendary rock band Queen and their song "Bohemian Rhapsody", noting that he wanted to bring something unconventional into the Cantopop scene.

The song takes its title from a newly coined slang term "MM7" meaning awesome or fantastic (Chinese: 正), which in turn originated from a typo committed by one of Lau's fans when typing the character using Sucheng input method.