Like the title, how does a band find their style. the style they want to play and sound good? Is it a case of trial and error or goign for something specific and not giving up until you get good at it?

In my band, we want to be mainly acoustic, but using the Loud - Quiet - Loud style like The Pixies and Nirvana. If this doesn't work at first, do we keep going with, or try a change?

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Pantera - Hellyeah - Rebel Meets Rebel - Down - Damageplan
Just go to by your intuition I guess?

It all depends on the members themself, I know a group and all of those guys are straight rock'n'roll just because they live that way.

Get some inspiration of bands like Mumford and Sons, etc.

The only thing you'll get on a forum as answer is just common knowledge.
I guess it's generally down to the style of song that you end up writing. Then when a song's been written it gets further little stylistic touches from the playing styles of each musician.
If writing songs in the quiet-loud style doesn't work then try out other things. Maybe don't approach songwriting with 'let's write a song with quiet bits and loud bits', try and just write whatever feels natural
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