Giggs will take charge of United for the first time on Saturday against Norwich, after being handed interim control of the team when David Moyes was sacked on Tuesday.
The former Wales international has been with United since the age of 14, making more than 1,000 senior appearances, and the club has helped him become the most decorated player in English football history.
Giggs spoke with the media on Friday for the first time since he was appointed, and he said: "I'd just like to say how proud I am to be managing for the remaining four games the club I've supported all my life and been associated with for 26 years.
"I've got to say this is the proudest moment of my life. The club has been the biggest part of my life since I was 14.
"I'm proud, happy, a little bit nervous, but just like I am as a player, I can't wait for the game on Saturday.
"I can't wait for 5.30 tomorrow when we walk out at Old Trafford. I know the place will be rocking. I've told the players 'I trust you and I know what you're capable of. Go out there and show it'.
"This is something I am going to enjoy for, what, two and a half weeks and bring back some smiles to faces of the fans.
"The players have looked really good in training this week, they are all excited as well. Everyone's looking sharp and I've just said to them 'enjoy yourself, give the fans something to smile about in these four games'.
"It's been a frustrating season and we want to end the season on a high. It was a shock to me on Tuesday when I spoke to Ed (Woodward) and he informed me David was leaving and then asked me to take over - it's been a whirlwind week for me.
"It's been different, it's been chaotic. I'm just getting a little taste, it's my fourth day in the job and you can never imagine what you have to do, what it entails becoming a United manager.
"I'd like to put on record my thanks to David for giving me my first chance in coaching. It's something I will always remember when he rang me in the summer and asked me to come on board."
Giggs said he couldn't yet think about taking over from Moyes on a longer-term basis, although joking that he had already given himself a new deal as a player.
"I'm just concentrating on the four games remaining," he added. "That's my main focus, the focus on tomorrow against Norwich, which is going to be tough game as they are fighting for their lives. After that I've not really thought about.
"I've just given myself a new five-year contract so I am using my power while I can. I haven't done much this week but I am still involved as a player as well and I've trained OK."
Giggs is keen to ensure his players return to the United philosophy of play which they became know for under Ferguson over the rest of the season, something Moyes faced criticism over.
"It's going to be my philosophy, Manchester United's philosophy," Giggs added.
"I want the players to play with passion, speed, tempo, be brave, show imagination. All the things I expect of a Manchester United player - work hard but most of all enjoy it.
"If I know I am enjoying the game, I'll express myself a lot more. That's what I'll be doing with the team tomorrow. Over these last four games I want to bring some positivity back.
"We've got three home games at Old Trafford where our form hasn't been great and I want to see goals, tackles, players taking players on.
"I want to get the crowd up and I want the passion that should come from being a Manchester United player."