4. Read Biographies.
Real life stories are good for your soul. I enjoy non-Christian biographies quite a bit.
However, stories of faithfulness are even better for your soul, and for your sermons. Whenever I read a biography, it finds its way into a sermon somewhere.
5. Talk to Members.
I am always illustration baiting. I like to drop my main point for Sunday in a conversation on a Monday or Tuesday with friends. I always get good and helpful input.
I have also dropped in on my kids during the week. There is nothing like trying to explain your main point to your kids. If they give you the cock-eyed dog look, then you can be sure you need to open a window or two to let some light in. Trying to explain the point via a story or illustration always helps.
These are just some ways that I have seen some movement from painfully predictable and redundant illustrations to surprising, fresh and (hopefully) illuminating illustrations.
Like adding some garlic or fresh basil to your meal, I can personally guarantee improvement if you strategically and intentionally fill your mind with things that are geared toward spicing up your sermon.