Just doing some reaserch
The riff of "My Sharona" was written by the band's guitarist, Berton Averre, years before he joined The Knack. He had played it and a drum groove for Doug Fieger, the group's lead singer and rhythm guitarist, who loved it and promised to make it a song. However, Fieger, with no lyric ideas to add, was unsure what to do with it beyond that.
When Fieger, who was 25, met Sharona Alperin, who was 17 at the time, she inspired a two-month-long run of songwriting, as well as becoming Fieger's girlfriend for the next four years. "It was like getting hit in the head with a baseball bat; I fell in love with her instantly. And when that happened, it sparked something and I started writing a lot of songs feverishly in a short amount of time." Whenever Fieger thought about Alperin, he would think of Berton Averre's guitar riff, and the two worked out the structure and melody from there. Averre was originally averse to using Sharona's name in the song, but Fieger wanted it to be a direct expression of his feelings; Averre ultimately relented.
Sharona herself appears on the picture sleeve for the single, and became a major booster of the band bringing many girls to their early shows. Sharona Alperin is now a real estate agent in Los Angeles, California