The Beady Eye singer explained that he does the minimum so that his voice is still raw.
He said on Absolute Radio: "I look after it a bit but not too much because I don't want to sound like Chris Martin.
"I remember Roger Daltrey from The Who telling me, 'Look, you've got to warm up.' I was like, 'Warming up, man, are you mental?'
"That was when I was about 25, and now I realise it's like that. You've got to warm up if you want to carry on singing. So I do warm up a little bit.
"None of that 'la la la' nonsense, no. I just sing a tune, man, on the guitar on my own and that."
Gallagher also admitted that he used to get lonely when singing for his last band Oasis because his vocals were always left to the end.
He added: "With Oasis, I'd be sort of at the end on my own surrounded by candles, like Aled Jones, singing on my own, just thinking, 'Is there anybody else in this studio?' It was very lonely, man."