Paul Lambert's side, who escaped relegation by just five points last term, have started the new campaign in better form and recorded a surprise opening-day win at Arsenal.
However, despite their improvement, Villa lost both their subsequent matches against Chelsea and Liverpool and Guzan insisted it is vital for them to be tougher to beat in order to avoid being dragged into another battle to stay in the top flight.
"We have taken the experiences of last season and made sure we have used them in a positive way," the American told the club's official website.
"For us now, it's about trying not to concede easy, soft goals. We want to make it difficult for teamsto score against us week after week after week.
"It's not a technical thing. It's just limiting our mistakes and being hard to play against every time we go out to play and upping our tempo offensively and defensively.
"You can't put your finger on one thing, it's a combination of things."
Villa's next Premier League fixture sees them host Newcastle on September 14.