The Villans battled against relegation for much of the Premier League campaign before putting together a run of positive results to keep themselves up.
"We had a tough spell but that was what made us stronger and helped to bring out our character," Guzan told the Birmingham Mail.
"When you go through those tough times you are able to help each other, pick each other up and dust each other down. You keep fighting.
"I think as a group and as a team we did a really good job of that and that will help us now in the future."
Villa travel to Arsenal on the opening day of the Premier League season on August 17.