As you know I recommend writing everyday. It doesn't matter what you write, just get something down on paper, disk or wherever. This will get you into the writing habit.
If you have a novel in you screaming to get out, start putting your ideas on paper. Some people write summaries, others just delve into the act itself. The form is up to you, though I recommend people with alot of ideas to write summaries. This was recommended to me by Christine Witthohn and her associate at the 2008 Cleveland Rocks Romance Writers Conference.
I took most of last month off and now am trying to get into the habit again. I should have at least wrote in my diary. There are many sites with writing prompts to get you started. I give prompts about 5 times a week on Y-City Writers' Forum.
There are so many ways to get inspired... Pictures and Paintings offer a wide variety of subjects to write about. Get out and observe people and make up stories about their lives. Nature offers something different everyday. Titles can inspire new stories. Wherever you find inspiration, jot something down.
Yes, this means you should always carry a pen and something to write on. I have a little composition book that I carry in my purse.
If you are serious about writing... Do it... Don't talk about it.