Johnson scored Sunderland's second goal at St James' Park as they recorded a memorable win in the North East derby to ease their Premier League relegation fears.
The 25-year-old has insisted that his side are far from safe at this stage but new manager Di Canio has filled them with enough confidence to improve and progress.
He told The Mirror: "The manager obviously gives everyone in the team confidence. He speaks to you individually and has spoken to me about things such as keeping the team's shape, he wants it to be perfect, because he believes if the team has good shape then we'll score.
"Our shape on Sunday was excellent, Newcastle couldn't live with us when we attacked. After the game he said to me that this is the start, and that for me personally it's going to get better and better, that this was the beginning for me at Sunderland.
"We are only, hopefully, going to go from strength to strength. I think there are a few teams that could still get dragged into the relegation fight. I don't think there was a better way for the manager to win over the fans, but they would probably have loved him anyway. Anyone with that amount of passion and love of the game is hard not to like."
Di Canio's men are three points clear of the relegation zone in 15th place with five games left to play in the Premier League.