By default I'm a lazy musician.
Most days inspiration doesn't just descend from the heavens; I have to work hard to get it and once I have it I have to use it quickly or it fades.
It's funny, believe it or not, often inspiration comes from looking at pictures of shows I've played, or pictures of other artists performing.
It stirs up that nervous/excited feeling in my stomach which makes me think "you should probably put the extra effort in so that you can keep playing shows". So maybe it's actually adrenaline that helps me write.
I've also found the op-1 synth to be very inspirational for coming up with little melodies and playing along with things I already have.
As far as emotion goes, often i'll have little scraps of melodies that I'll start to assemble and from there thoughts, images, emotions start coming to mind from that. And then i'll develop those melodies in accordance to those thoughts, feelings, etc.
Hope that helps somehow.