Some writers methodically plan their stories out, others fly by the seat of their pants! I have to say I am asked this question a lot and I always reply both! I fly methodically!
When I get an initial idea, I love pant seat flying! Methodical planning when I’m in this kind of mood inhibits my creative flow, so I’ll write and write and write, up to 6000 words a day!
But sometimes you’ve got to try and gain control of creativity otherwise it doesn’t always make a whole lot of sense.
When starting my writing day I always read through what I wrote last. And more often than not there are a lot of mistakes and sometimes what I’ve created and thought was utterly amazing isn’t even comprehensible! At this point planning can help creativity!