It helps to be conscious of your process — even if that merely means knowing what you're doing right now.
When I meet with clients, we set goals for what will happen before the next time we meet. Sometimes that means a certain number of words will be written or that they'll draft a certain chapter. Sometimes it means they'll have put in place their intended workflow and rhythm of work on their book or that they'll have put together their workspace.
When connecting with potential clients, I usually lay out some options for moving forward together and a step-by-step framework for how our work will proceed. Then they get to choose the option they want and will know what happens next.
The point is, it helps to have a plan. A plan brings clarity and purpose to your process. It also helps you rest, in a way, because it frees you up to simply work on what's in front of you.
Do you create plans for your book work? What does your plan include right now?