You might as well start today if you already published your book.

Start thinking like a pro-author.

Start a list of people to whom you can send your book.

Start connecting with people here.

Start asking for reviews; yes, keep asking.

Start working on your website and optimize it.

Start by taking one action today to move your work forward.

Do not overthink everything or wait for something else that is outside of your control to be done before starting with something simple.