One influential aspect of publicising a novel is the use of 'tags'. I learned about tags when I began self-publishing my short stories, novellas and poetry on Smashwords. Mark Coker, the founder of Smashwords, offers a lot of good advice in 
his free ebooks on style, marketing and publishing.
Tags are one-word descriptions that apply to your novel, which readers use to find ebooks of interest to them. You may be going for a traditional publishing deal, but it's still worth thinking about how your story would be sold using tags; they are a simplified version of the blurb that appears on the back cover—keywords that stand out, grabbing the reader's attention.
Thus, my latest psychological thriller would have the tags:
Murder  Mummification  Stone Baby   Poison   Madness   Promiscuity   Deceit   Beast of Bodmin Moor  Sex Lives    Urban Legend   Ghosts   Farming
Readers browsing for ebooks can search for stories with these themes. Tags are a useful thing to bear in mind as I write, for they may help someone find my novels, whether they are online or jostling for attention on a bookshop shelf—the dreaded process of discoverability.
Just think, what someone asks you when you tell them you've written a book: 'what's it about?'
 Tags are the shorthand answer.