Beginning a novel is a daunting task. There are so many decisions to make that it can be frustrating just to decide what genre you want to write in. Every author has unique talents and abilities that might direct their storytelling towards a particular genre. But how do you find yours?
Writing is not only an act of love; it is a long process full of edits and revisions. You should make your story something that you have passion for. When you sit down to read, what kinds of books do you like to pick up? What kinds of movies interest you? What topics are you an expert on? Analyzing your own entertainment preferences can help you narrow down the list and find out what makes you happy.
Don't choose a genre simply because it is trendy at the time. Not only will you have a more difficult time writing a story you don't care about, but the genre may be out of style by the time you finish your book! The publication process is long and, even if your work is accepted by a publishing house, it can take up to a year for it to appear on bookstore shelves. Trying to predict what will be the current fad that far into the future is nearly impossible.
Keep a notebook of the ideas that pop into your head. Even if you only jot down a sentence or two, this record will help you choose a new idea when you are ready to start a new project and discover what genres most interest you. Read through your notebook and make notes in the margins of what genre might best suit the idea. Do you see any patterns forming? If you are constantly coming up with ideas in one particular genre, don't fight your muse. Write them!
Genre is ultimately about marketing, not writing. It helps categorize the writer into a place on bookstore shelves. Authors often feel pressure to write future books in the same genre as their first simply so they can build a following of fans. It can be difficult to maintain an audience if your books are widely varied.
But remember, just because there is pressure to continue in one genre does not mean you have to follow it. If you want to write in multiple genres do not feel obligated to limit yourself! Many published writers have books in a variety of genres. You may wish to take on a pen name for one or more of them (for marketing reasons) but it is certainly an option.
When you begin a first draft, don't worry about what others expect you to write or what you think might sell. Just write for yourself and have fun!