Kelly was one of the standout contestants in last weekend's launch show, performing his own acoustic version of 'Make You Feel My Love'.
Despite wowing Simon Cowell and the other judges with his vocals, Kelly insisted that he doesn't regret applying for BGT rather than the singing series.
"Playing my own music is a massive thing me. I learned to play instruments before I could sing. Originally I played the drums actually," he told Digital Spy.
"But I'm never comfortable without an instrument. I think if I'd gone on X Factor without a guitar I'd have made a proper fool of myself.
"It isn't just hiding behind it, though, it's an extra way of expressing myself through the song. It's a lot easier to put your own spin and feeling on a song if you can dictate how a song goes."
> 'Britain's Got Talent' Sam Kelly: 'I was scrounging around before the show'
Kelly also revealed that he is hoping to showcase his piano skills if he reaches the semi-final shows. "I don't want to do something for the sake of it, but if it helps the song and it's right for the performance, I'd like to do it," he said.
Talking about his nerves at playing in front of Cowell and the panel, he added: "It was a pretty surreal experience anyway, but the way Simon is staring at you in a calculated way, it's terrifying.
"I had all sorts of awful thoughts going through my head and I thought, 'Oh my God, I've mucked up, why am I doing this?' It is hugely intimidating performing for him."
Britain's Got Talent continues on Saturdays at 8pm on ITV1.
> 'Britain's Got Talent' winning YouTube battle with 'The Voice' UK
> 'Britain's Got Talent' live blog
Watch Sam Kelly's Britain's Got Talent audition: