Aguero believes the FA Cup offers City a great chance of silverware with a quarter-final against Championship strugglers Barnsley on Saturday week.
And the former Atletico striker, who clinched the title trophy in the dying seconds in May, said: "Let's take it step by step.
"Take the FA Cup, each victory means we are a step closer to winning the competition.
"It's about keeping focused and trusting in our game. That applies to all our remaining Premier League games too.
"Can we still win the title? I'd like to believe so. We can't give up, even though it looks tough."