The Take That star organised the commemorative concert that was held at Buckingham Palace and said that he was very pleased with the process and its outcome.
The star-studded show, which took place on June 4, took 19 months to plan.
As well as organising the concert, Barlow composed the special Jubilee track 'Sing' with Andrew Lloyd Webber and performed duet 'Need You Now' with Cheryl Cole.
Barlow was asked by GQ magazine what the highlight of 2012 has been. He answered: "It's got to be the Jubilee. Really it has. So many of the artists were coming in and saying, 'This is brilliant! I can't believe it!'
"You look down and there's Prince Charles. The crowd was all down The Mall - as far as you could see, people's heads.
"Now I just sit and think, 'That's probably as good as its gonna get'. I'm still celebrating."
The 41-year-old said that the occasion was "surreal", but also admitted that he hardly got to watch any of the live performances because he was so busy.
Speaking of the OBE he recently received from the Queen, Barlow said: "I never want to get to the point where I think, 'I've done it all now and I've been awarded - I'm done, good night'.
Photo gallery - Diamond Jubilee Concert:
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