The practical question that you should ask yourself before you begin writing is “Who are my readers?”
Understanding your readers isn’t as hard as it sounds. Often, we are drawn to write the books we want to read. Those who would enjoy these books will have similar tastes as you and are likely to be a lot like you. Knowing your audience can be as simple as understanding yourself. Even if you write for a different age group (for example, children), this still holds true. You should know the age bracket and gender of your main readership, their desires, their identifications, and their beliefs.
I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.