Stevens was chosen as Thomas Schneider's replacement at the Mercedes-Benz Arena on Sunday after they drew 2-2 with Eintracht Braunschweig a day earlier.
Prior to that, Stuttgart had lost eight Bundesliga matches in a row with Saturday's draw ensuring they sit 15th with 10 games remaining.
However, Stevens, whose tenure at Greek side PAOK ended earlier this month, is ready for the challenge and called for his squad to focus on the task ahead as they fight the dreaded drop.
"I know it's a challenge, but I'm up for it," he told a press conference on Monday.
"As soon as I heard from Stuttgart, I didn't need long to say yes. I felt ready.
"There's going to be an incredible amount of work to do in the coming games and I'm going to talk a lot to the players.
"Our only priority now is to stay up and we need to focus all of our efforts into that. We need to be united."
Stevens will take charge of his first game as Stuttgart boss on Saturday when they travel to Werder Bremen.
