Shelvey, alongside former Scotland international Matt Ritchie, inked a new deal at St James' Park until the summer of 2023 this morning.
“Steve has been a breath of fresh air for me since he has come in," Shelvey, who has scored five goals this season, told NUFC TV.
“He just asks one thing of you and that is to work hard. I feel like I have been doing that this year and every time I have been fit I have near enough played.
“I have just got to keep going, working hard and not looking too far ahead."
Shelvey also revealed a key factor in his decision was how settled his family are in the region, stating he 'feels safe' living in the North East.
“It has been rumbling on for a while now and I am glad it is all done with so I can get on with my football now," he added.
“This is the longest I have been at a club and I feel settled. I am looking forward to spending many more years here.
“It has been good. I needed stability at a football club and I have got that now so it is a credit to the club and the fans have been spot on with me as well.
“I am looking forward to giving it my all. I feel safe up here. It is a lovely place to live, it is a good place to bring the kids up and my family see it as somewhere to visit as well.
“I tend to stay up here rather than going home. It is five hours away from home but it is a place we all feel settled."
He continued: “I have never had any intention of leaving the club.
“I have always stated my intention to stay at the club and it is just about enjoying my football.
“It is now just about guaranteeing survival and then looking to kick on."