The number of voice recordings on my phone is ridiculous...Each containing lyrics, a rhythm or chord progression that have been long forgotten.
When I write music it is often a spur of the moment situation! I'll have an idea for a cool lyric or melody and keep going until I have some sort of shell of a song.
I do enjoy playing around on a guitar or piano - it's a FAB feeling when you find something just just feels right!
There's absolutely no structure whatsoever to how I write music though - sometimes I'll start with chords and other times I'll have lyrics and melody that I think sound aright!
Basically I wing it...I don't know if that's reflective in my music but there isn't structure to how I write at all!