A very important consideration for all authors is what genre does your book fall into?
I recommend visiting a book store to make a note of the genres as listed on the shelves.
Which one will your book fall into?
If you can’t categorise it, then the book store manager will not know where to put the book, so it might end up getting lost on a shelf where it doesn’t belong.
My company published a series of novels by one author which was categorized as Visionary Fiction. Most book shops don’t have a genre like that so her books generally ended up in Fantasy or Science Fiction, neither of which is correct.
Visit several bookshops if possible because every book shop caters to a different market.
Take a note of how many books are on each of these shelves to get an idea of your competition and the popularity of the genre.
While you are there do have a critical look at aspects like cover design and how the books are laid out.
As usual, there are trends and fashions in book design. Also bear in mind that design styles are different for every country. In the USA the popular trend has been for covers featuring fancy graphics and fonts with a small but impactful image on the front cover. whereas the UK and Europe are generally more conservative.
The United States market remains huge and very important so their influence has to be taken into account.