The Brazilian is confident he can recapture the form that made him one of the best players in the world, but he needs time to adjust.
The 31-year-old returned to Milan on a free transfer on Monday and made an immediate impact on his debut, assisting Antonio Nocerino's goal in Saturday's 4-0 friendly rout against Chiasso.
And after a troubled four-year spell in Madrid, Kaka insists he in on course to emulate the form that first elevated him to prominence in his initial spell at San Siro.
"It was a good game today," he told reporters after the match. "Milan need to improve but we have room for growth.
"From my personal point of view, at age 31 you have learned a lot of things and now I choose plays that are best when passing the ball.
"I missed just a little rhythm and continuity but I'm happy."
Rossoneri boss Massimiliano Allegri was likewise enthused at the promise shown by his latest signing, who was handed the captain's armband for the game.
"Today Kaka played more as a midfielder and just needs to find the rhythm to his game," the Italian added. "[Riccardo] Saponara came back fine, he's fine too. He needs to play and find the right condition.
"We have an excellent department of attack, with different solutions to deal with every game when the players are in good condition.
"We play once every three days and we will need everyone."