I get into "composing mood" when listening to great pieces of music literature. I say to myself: That was really great! Can I do something similar?
I always start immediately with notation; I got used to hear full orchestra as it sounds when composing for it. I don't do it by piano unless I compose for piano. At first, the formal approach is too short so after listening to what I wrote I get in between and make it longer, bar by bar until I am satisfied.
I prefer composing "absolute music" but I have also written several programmatic works. And it's easier to find title when doing programmatic music. My titles are usually traditional. I love composing concertos, symphonies, sonatas, sonatinas.