Focus.
My brain is constantly under a barage of ideas, some work, some don`t.
I tend to try all of them, make a lot of sketches, and pick the best ones, and go back and focus on them.
There is no method, sometimes minimal works, sometimes huge layers of sound can work.
I can`t really think of any advice in terms of focus, as we are all so different.
Believe in yourself, and suck up knowledge like a sponge.
That`s all I can say.