One of the best things you can do for a completed draft, whether it’s the first or the eighth, is to step away, way away. When we’re involved in a big project, the ideas or story lives in our head and we go on working it subconsciously even while we’re at our day job or taking a shower or doing the laundry. We mull it over and make changes and additions and we get so close to it, that we can’t see it anymore.
That’s when a vacation is due. Maybe that’s a literal vacation where you travel and see new things and make notes for a new piece of writing. Maybe it’s a sabbatical and you turn your attention to cleaning out gutters and organizing the garage or the basement. Maybe you take a class in a related or completely different writing technique or other art medium to fill the creative well. Maybe you read in a different genre, getting a feel for epic poetry or Russian fantasy novels in translation, anything but murder mysteries, since that’s what you’ve been working on.
While a hiatus of a few days is good, a hiatus of several months is even better. You’ll step back into the novel with a more critical eye, with an ability to discern solutions to the bigger issues, and a way to resolve the sticky issues that have been plaguing you. And if you’ve started a new writing project, so much the better. Working on two pieces at once can give you all kinds of great ideas and keep you from getting stale on one.