The 40-year-old Welshman is manager for the season's final four Premier League games after David Moyes's sacking.
"I am proud, I am happy and a little nervous," said the midfielder at his first news conference as boss.Giggs, the Old Trafford club's most decorated player, wants to secure a Europa League place next season for the club, who lie seventh in the table.
Giggs appeared relaxed and jovial as he addressed the media at United's Carrington training base, saying he wanted to "bring back some smiles on the faces of the fans".
Ahead of Saturday's home Premier League match against Norwich City, he said:
- His first call upon being appointed was to former United boss Sir Alex Ferguson: "I wanted advice and I wanted to know just what to expect."
- That he had not thought about his long-term future: "My mindset is on Norwich first and then the remaining three games."
- The mood in training has been good all week: "I can't wait for Saturday. I know the place will be rocking and know the fans will be behind us."
- Everyone at the club wanted a successful conclusion to the season: "It's been a frustrating season and I want to end it on a high."
- The team would aim to play an exciting brand of football: "It is my philosophy and it is Manchester United's philosophy."
- Jokingly that he would boost his own playing role: "I've just given myself a five-year contract while I can."
- Was grateful to Moyes: "I'd like to thank David for giving me my first chance in coaching."
Giggs came through the youth ranks at Old Trafford and was part of the famed 'Class of '92' that helped contribute to so much of the club's success under Sir Alex Ferguson.
"I have got to say it is the proudest moment of my life," he earlier told the club's MUTV channel.
"I have supported Manchester United all my life, I have been a part of the club since I was 13. I am proud, I am happy, a little nervous and, just like playing, can't wait for the game on Saturday."
Giggs has played a record 962 times for United, and will be assisted in his managerial duties by former team-mates Phil Neville, Nicky Butt and Paul Scholes.
"My philosophy is the Manchester United philosophy. I want players to play with passion, speed, tempo, to be brave, with imagination - all the things that are expected of a Manchester United player," he said.
"I want to see goals, tackles, players taking players on and getting the crowd up. I want the passion that should come with being a Manchester United player.
"I'll tell the players just to try to enjoy yourself, express yourself. I just want them to enjoy themselves and give the fans something to smile about in the remaining four games."
United began the 2013-14 season as champions, but currently trail leaders Liverpool - who were seventh last season - by 23 points.Moyes took over as manager in July 2013 after the retirement of fellow Scot Ferguson following 26 years at the helm in which he won 38 trophies, including 13 Premier League titles and two Champions League crowns.
Moyes guided the side to the last eight of the Champions League this year but they cannot finish in the Premier League top four, ruling them out of a place in Europe's top club competition next season.
Qualifying for the Europa League is not necessarily in Manchester United's hands.
With Manchester City having won the Capital One Cup, the club finishing in sixth place will secure a Europa League place only if City finish in the top four and take their spot in the Champions League.
United are 12 points adrift of fifth-placed Everton - and cannot catch them - and they have a six-point deficit to sixth-placed Tottenham with a game in hand.