Rooney, a player-coach at Derby, has shared responsibility of the first team since Phillip Cocu was sacked earlier this month.
Hindered by a points deduction, Derby are bottom of the Championship table, six points shy of safety and winless in nine.
With a takeover imminent, the club have made a change, promoting Rooney in a decision the new interim coach hopes will provide "clarity".
Rooney, who will not play at home against Wycombe on Saturday, revealed technical director and former England boss Steve McClaren - returning to Derby this week - was "part of that conversation".
"For the two previous games, the four of us did it together, preparing the team and picking the team together," Rooney said.
"We felt that it needed one voice, one person to do that and make the decisions on the team, the starting team and obviously the subs coming into the game.
"We felt I felt I was the right man for that. That's where we're at.
"It's obviously exciting for me to do that. Management is something I've always said I wanted to go into. It's an opportunity for me to try to pick the right team to get us a positive result."
Despite his eagerness to kickstart his coaching career, Rooney refused to look beyond Saturday's match.
"Tomorrow is so important to us that we have to focus on tomorrow," he said. "We can't focus on what happens in the long term just yet.
"There will be conversations, obviously, but we have to focus on tomorrow and can't look too far ahead. It wouldn't be fair on the players to be looking at what happens in the next few weeks.
"We have to solely focus on tomorrow's game and then the new owners will be in, I'm sure, in the next few days. Once that's complete, there will be conversations and we'll see where that goes.
"I wouldn't sit here and say I'm auditioning myself for the job. This football club deserves better than that. It deserves better than someone saying they're having an audition."
Rooney believes he could not juggle the new role with playing - at least for now.
"Obviously I played the last game, but if I'm making decisions on who plays the game and doesn't play the game and the preparation of the team, I wouldn't be able to give it my full attention and still be part of the game," he said.
"I won't be involved in the game tomorrow. I'll be focusing on getting the team right to play the game."
Asked if he would miss the opportunity to use a player of his talents on the pitch, Rooney replied: "Of course, but as I said before, this is what I want to do, this is what I see myself doing.
"As much as you'd like to carry on playing for as long as you can, there comes a point where you have to make decisions. For tomorrow, I think it's the right decision."