A late Callum McGregor strike secured the win in the first leg of their Champions League second-round qualifying tie on Tuesday, and Deila is keen to see more of the same from his players in future games.
"I am happy that we won the game but most happy with the performance," the Norwegian, who took over at Celtic last month, told reporters. "I love to win and I am here to win but I need performances. I want to win in a certain way as well.
"Today was a step forward in the way we want to play and that is what I am most happy about.
"We deserved it, we deserved more. I am getting energy out of this, I like what I saw in the second half."
Celtic host Reykjavik in the second leg next Tuesday.