Mancini believes that regular meetings with director of football Txiki Begiristain, in charge of transfers, will see City succeed in the market before the start of next season.
He said: "We need to work now so it's not like last year.
"Now is the time we can close in on good players. I have had meetings with Txiki every week now about the summer.
"If you wait until May it can be impossible because all the good players are gone."