The 18-year-old missed out on the final of the 1m springboard in Barcelona earlier this week as she finished 19th overall.
But having qualified from the 3m springboard preliminaries in fourth place, Starling then held her nerve in the semi-final to take 12th position and the last qualification spot.
She started off slowly in the iconic Piscina Municipal de Montjuïc but moved up to 11th in the third of five rounds, needing a score of 54.95 from her final effort to qualify.
She surpassed that comfortably, scoring her joint highest score of the list with 61.5, to give her an overall score of 297.35.
Coached by Edwin Jongejans, himself a former world champion at the 1m springboard, Starling was thrilled to have made her maiden final, coming just 12 months after she narrowly missed out on last year’s Olympic medal showdown.
"I am just so happy to finally not be 13th or 19th or fourth," said Starling, whose fellow Brit Alicia Blagg was 18th in the semi-final.
"Diving is fun and I'm not going to hide the fact that I enjoy it. Sometimes I don't understand why everyone is so serious.
"If you just zoom out on the world it's just incredible to be here and I just love every second of it and I just smile and enjoy it. I'm really excited about the final.
"I did not think I had made it. I came out thinking I was going to be 14th or something as I did not have the best competition out there so I was really happy to end up 12th.
"It gives me confidence having Edward there. You know you can trust him because he has been there, done it and he knows exactly what you are going through."
- Sports & Recreation