Often the best thing to do is take some time out before revisiting your thesis. You've invested a lot of time, intellectual and emotional energy in writing it – leave it for a while and then look at it with fresh eyes. It's also a good idea to talk to colleagues, particularly those who have been published before. Then it's about pinning down the core subject of interest in the work, remembering you will need to make some tough decisions.
What's unique or interesting about the work?
Theses can delve into sometimes arcane subjects in great depth, or range across a variety of subjects to make links between them. Reworking for book publication may mean providing less detail and more context about a subject, or, alternatively, writing more about fewer themes or ideas. Ultimately you need to identify what is the key concept or argument that you want to communicate — what's unique or interesting about the work — and focus on that.
The following activities are designed to shape your thinking about how you might approach the task of reworking. They may also be helpful when it comes time to prepare your book proposal.