One of the best pieces of advice I’ve heard from professional writers is to work on multiple projects. It may seem like it would be best to focus on a single novel or piece of writing at a time, but having at least a few projects can be helpful for many reasons. If you get stuck on one piece, you can easily set it aside and work on something else. You may also find that if you keep your creative juices flowing as you transition back and forth between projections, it becomes more and more easy to keep the muse at your side.
I personally don’t wait for the muse. She can be very fickle, so I tend to sit at my desk and work, and figure if she shows, fantastic. If she doesn’t? That’s okay too, because I still got some work done. Most of the time I find that my work is pretty comparable, whether or not the muse felt like joining me that day. I enjoy that free flow, that feeling of inspiration as much as the next writer, but I’m not going to wait for it to strike. I’ve got work to do, and I am betting that you do as well.
The Taming of the Muse 