I have just been listening to On Writing : A Memoir of the Craft by Stephen King. He talks about the importance of 'Working with the door closed'. Meaning that, until your story is down on paper, from begining to end, don't show it to another living soul. Make it, then show it later. I am guilty of getting over excited and showing my ideas before they are ready, then being knocked way off course by other people's opinions.
Allowing yourself time... For the last few years I have worked with a timetable pinned above my desk that shows all of the projects I have lined up, sometimes going three years in to the future. For a few years I liked this situation, it made me feel secure. But graudually I started to feel scared of that looming timetable. I had no time to play or create for the sake of it. So I asked one of my publishers if I could pay back my advance (and they very kindly said yes), I turned down a two book deal in favour of a one book deal, and said no all other offers that came along for a while. I can't tell you how good it felt, it was such a relief. And now new book ideas are springing up everywhere.
There is a good article on the pros and cons of deadlines here.
Here is a link to something I have been enjoying whilst working recently. Chris Watson's album Weather Report. I find it hard to listen to music while I work, but his recordings of nature take me into another world, which is exactly what I need whilst I write. Let me know what you listen to, I am always on the search for inspiring listening.