His first performance was in 1973 for the celebration of the birthday party of Kool Herc's sister Cindy.

"La Rock had no stage name and performed out of sight from the audience, so no one knew who was doing the rapping. His original raps were shout-outs to his friends, before the actual poetry emerged in his lyrics. He originated phrases such as "You rock and you don't stop" and "Hotel, motel, you don't tell, we won't tell" (which was later used in The Sugarhill Gang's single "Rapper's Delight")" From Hip-Hop-Music

His rapping style emerged from initially being entirely improvisational
and merely for fun like shouting out friend's names and according to himself
"Pretend[ing] dudes had double-parked cars [...] to impress the girls"

To incorporating more poetry and rhymes as well as
rehearsing some lines and lyrics before performances.

"As other nascent hip hop groups patterned themselves after Herc and La Rock and improved on their formula, the popularity of the Herculoids began to fade as early as 1977. After Kool Herc was stabbed at a party, La Rock decided to step down from hip hop and let the younger generation move in. Since he'd had a long run lasting several years of being on the top of the Bronx hip hop scene, La Rock didn't want to continue if murder was going to be a part of it. " Quoted from Hip-Hop-Music