Be persistent, though be patient with it. Guaranteed you won't finish half the story in one night obviously, but you can certainly make a dent. Also when it comes to publishing, don't let any rejections discourage you. I'm not saying your writing is horrible; hell, I haven't even read anything of yours. I'm just saying that sometimes it takes a few tries to get an acceptance from a publisher - so never scrap a story when feeling discouraged.
Support from friends, family, or even strangers like you and I, is awesome for motivation as well. Try to find your inspiration, brainstorm as many ideas as possible, and you're set. It's all uphill from here.