If you are stuck for your next chapter, put on a headset and dictate as much as you think will be needed in the chapter to advance the plot and/or character development: any and all ideas and thoughts, bits of dialogue, etc. For me, this is especially useful first thing in the morning before all other stuff absorbs my attention (such as making a living). I always find some gold in those words on the page later and I feel some sense of writing accomplishment for the day.