The Norwegian will start putting his squad through their paces later this month.
And Under-20 boss Kennedy said: "It'll be a big pre-season for everyone involved, whether it's first-team players, youth players or anyone else around the club.
"Moving forward, there will be players coming in and it's important to make an impression to make sure they are in his plans.
"The manager will want to hit the ground running and make his own impression on the players, which I'm sure he will do. He's a very positive person and I think the players will respond to him and to what he wants.
"It's a big change for the club but it's fresh and something we can look forward to.
"He [Deila] spoke very well when he was unveiled as the Celtic manager and anyone who has spoken to him has been very impressed.
"He's a humble guy and very down to earth and he's someone who wants to learn and develop.
"He knows what he wants and how he wants to do it.
"It is important to have a clear vision of how he wants to move the club forward."