City defeated Arsenal 2-0 at Wembley on Sunday.
Bernardo said at the final whistle: "The first 15 minutes felt difficult, they were able to create a big chance where James Trafford was amazing for us. Second half we tried to go for them a bit more. We felt they lost a bit of energy and when we felt that we had to go even more for them.
"Nico O'Reilly is really good at arriving in the box in those moments. We were lucky to score the first one and when we are on top we can find the spaces.
"In a final you know both teams are going to have momentum. Arsenal's was the first 10 or 15 minutes. In those moments you fight together to make it as short as possible. We have the firepower to go for them as well.
"I try to help the team as much as possible. I now how the manager wants to play and I always try my best. Beating this team is not easy, they are a fantastic side.
"With the players we had today, our job was to give as much stability as possible to the team. We wanted to stay stable, stay compact, not make stupid mistakes. Overall it was a very good performance."
On City's young players winning a first trophy, he added: "To get the first trophy releases a bit of pressure. It also makes you feel well and you want to repeat that feeling."