Richard Marek is a book editor, a book publisher, and the author of the novel Works of Genuis.
Write one page upon arising. Only coffee permitted. Stop writing when page is completed, even if it's in the middle of a hyphenated word.
An outline! Carefully prepared, so things planted early pay off later. And write character sketches if you're embarked on a novel.
Read. Read, read, read. READ. The best guide to writing I know is John Gardner's The Art of Fiction. It sure helped me!