The 'Back For Good' hitmaker has reflected on his time in the boy band ahead of his 50th birthday on Wednesday (20.01.21).
And he's admitted he and his bandmates - which originally included Robbie Williams, Jason Orange, Mark Owen and Howard Donald when they formed in 1990 - "wince" when they look back at old pictures because they weren't afraid to bare some skin and look "stupid".
Gary told SiriusXM: “We were on the covers of magazines before we had any hits.
“Our 90s incarnation, we look back at that period and wince. We were really selling sex.
“I remember being side of stage at Wembley and Howard had trousers on that had no bottom in it. And I thought ‘Where are we going with this band?’
“We were like a show band. We were never afraid of looking a bit stupid or camp or anything.”
Elsewhere, Gary admitted he lost all his confidence and even forgot how to write songs when his record label dropped him after his second solo album, 'Twelve Months, Eleven Days', flopped.
He recalled: “I left the UK in the mid 90s, high on confidence after writing the then song of my career, 'Back For Good', and I toured the world for five years. I was in the best shape. I then signed for someone who had a different idea."
He added: “I actually lost pretty much everything and forgot how to write a song.”
Gary previously claimed it took him just 15 minutes to write 1995 hit 'Back for Good', but these days, Gary wouldn't relish the pressure of working under the kind of tight deadlines usually imposed by record labels.
He reflected: "You do it just because that's what you've been told to do. You don't think, 'Wow, this is so much pressure, everyone. How can I do this?' You just get on with it.
"I was full of confidence at the time because we were having hits all over the world. And that is a good place to be as an artist."
Despite his early successes, Gary doesn't miss having to work under such pressure and admitted he's not as confident as he used to be.
He added: "I'll be honest, I don't think I've got that kind of confidence anymore.
"I'd have been 20 or 21 when those calls used to come in. And that's a different person.
"I wouldn't trust myself now to think I could do it in a week."
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