The Dane, who cost the Bluebirds a then club-record £8m when he arrived from FC Copenhagen in the summer, has been limited to just three Premier League appearances due to an ankle problem suffered in August.
"I have been training with the team for a couple of weeks now," he told Ekstra Bladet. "It's going well and I am keen to show what I can do. But I am fully aware that I have to prove myself before I get the chance to play from start.
"I cannot expect to play from the start when I have just recovered from injury. But it is only through my displays that I can convince the manager to give me a chance. I have got patience and I hope that the chance will come."
Cornelius, 20, scored 18 goals in 32 appearances for Copenhagen last season.