The Citizens will host the Blues at the Etihad Stadium in the Premier League on Monday.
"I think that the most important thing is to do your talking on the pitch when you play," The Mirror quotes the Chilean as saying. "Every manager can do whatever he wants but, for me, I have my own way of doing things.
"I do not know what Mourinho has said about us and I have no comment to make about him. I always tell my players that it doesn't matter who we are playing or whether we are home or away. What is important is that we try our best from the beginning, that we have a winning mentality and that we work well with and without the ball.
"In the last match against Chelsea we made a very important mistake and we lost the game. But we have improved since then. All the statistics say we are improving. But I have told the players that they must continue to improve."
City are currently at the top of the league table, while Chelsea are three points behind them in third.