The 38-year-old German was speaking at his first press conference as Newcastle head coach on Tuesday following his appointment as Eddie Howe's successor.
Jaissle cut a calm figure during his unveiling at St James' Park and began by greeting reporters individually, but he acknowledged that his demeanour can change significantly during matches.
"I will not change my style because that's my personality," he said. "On the touchline, I am emotional, but I need to respect the box (technical area) a bit more."
The former RB Salzburg and Al Ahli coach also joked that he may need to adjust to the Premier League after working with a larger technical area in Saudi Arabia.
"I'm a bit scared," Jaissle said. "I hope in the beginning the referees can maybe close their eyes here and there a little. I need to learn that."
His competitive nature has been evident throughout his career, while his playing days ended at 25 because of a serious knee injury.
Former Hoffenheim team-mate Chinedu Obasi described Jaissle as someone who was always driven to succeed.
"Matthias has always been very hungry," Obasi said. "He's had that leadership style and been vocal and passionate about the game. He wanted to win."
That mentality helped Jaissle win Austrian titles with Salzburg before guiding Al Ahli to successive Asian Champions League crowns.
He said ambition was one of the main reasons he accepted the Newcastle job.
"We are ambitious. That's the most important thing, also why I decided to come here," Jaissle said.
His first days in charge have included a training camp in La Manga and a 2-1 pre-season victory over Valencia, while Newcastle supporters have already welcomed him with a chant based on Baccara's "Yes Sir, I Can Boogie".
Jaissle said he had been impressed by the reaction.
"The welcome from the fans was unbelievable when I was having a walk yesterday in the city," he said. "It was really giving me a nice feeling."