My own personal process:
Imagine I'm sat with some bongos. I'm playing the rhythm that's my own. It's hardwired into my subconscious and I can play it with my eyes closed at this point. But supposing I want to test drive another rhythm? Who's rhythm? If I draw on myself, the rhythm will inevitably end up being the rhythm I always use. So, I take the main character and imagine how they'd play the bongos.
At first that rhythm is all over the place. My hands fight me to return to the rhythm familiar to me. Rather than allowing that to happen, I place down placeholder words and phrases, just to keep the new rhyme flowing. I can usually get close to learning the new rhythm after a couple of pages. Until then, it's a fight between myself and the protagonist. I always let the protagonist win.
Once I've got that rhythm more or less nailed, I consider style, and just like rhythm, I ask myself: how would the protagonist write this? They'd use different words, different phrases, different metaphors, similes etc. Those are all informed by the personality I've imbued the main character with. This new layer is then layered over the first two pages and tightened until it resembles something close to decent.
This is also informed by genre. I often go on YT and listen to a good reading of a particular voice: Fantasy, horror, children's stories, detective novels etc. before I start the process. My main structure of thinking is Genre (YT vids), rhythm (genre+protag), style. (genre+protag).
The big test is then just to let it flow and see what happens. If it flows naturally, result, if it falters and loses the rhythm/style, repeat the process from the beginning.
Each new voice then offers up unique puzzles to solve, and solving them adds more to my arsenal for when I eventually return to the familiar rhythm naturally mine. I've set myself a year before I return to that.
So, what is your method?
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