The St Pat's junior - who plays both fullback and halfback - missed out on getting a run with the Sharks' SG Ball Cup team earlier this year, but due to the competition being extended from under 18s to under 19s next year because of the coronavirus pandemic, he'll have another crack at been selected in the matchday squad.

Colley said it's a humbling experience to resign with the National Rugby League club.

"It's good and really humbling," he said.

"It's pretty rewarding for my hard work too. I've put in a lot of hard work, so it's good to get something out of it."

He said his main target is to crack into the SG Ball Cup squad for the Sharks and then go from there.

"I went down last November to try and get into the [SG Ball Cup] squad and I got into the top 25, but I didn't get a run in the top 18," he said.

"Last season was something new. I didn't know what to expect but now that I've been down there for that year, I want to probably go back down again and put in a bit more of an effort and get the most out of myself.

"I want to get into the SG Ball squad and run the ball more and have a good impact on the team."

If the Cronulla selectors have any doubts about Colley's skill, they just need to look at his form this season.

He played an instrumental role in St Pat's run in the Western Youth League, which ultimately resulted in a semi-final defeat to Dubbo CYMS last month.

His form has been so good that he was recognised as the competition's best and fairest player in 2020, being presented with the award on Mid West Cup grand final day last month.

"Mum and dad knew but they kept it a surprise for me," Colley said on his accolade.

"I went to the grand final between Oberon Tigers and CSU Mungoes and they said I have to get dressed up. I was going to anyway because it was so cold, so I didn't mind.

"After the game they announced me as the Western Youth League under 18s player of the year. I couldn't believe it.

"I had a big smile and it was pretty surreal."

And looking ahead to 2021, the 18-year-old - who has been playing for St Pat's since under 11s - is already keen to crack in with the Sharks down in Sydney.

"There's some great facilities down there, like big gyms for their players and fields to train on for their juniors and seniors," he said.

"The game is so faster, bigger blokes, the foot work. It's a different level of footy and it took me a couple of weeks to get use to.

"Once I got use to it, I found my feet and I sort of didn't look back."

It remains to be seen if Colley has played his last for St Pat's, with Cronulla yet to confirm whether he'll be allowed to play in Group 10 in 2021.

"That's something I spoke about with the club when I went down a few weeks ago to resign," he said.

"They said, 'We'll get to that when we get to that'. If I have a good year in SG Ball, I might get pushed into Jersey Flegg."

Some of Colley's experience includes representing NSW Country and Western Rams at a junior level.