In this video, Janet Syas Nitsick and I discuss research when you’re writing your book. Some people like to research before they start writing their book, and others like to start the book and research as they go along. You need to do the best method that works for you.
Possible avenues of research is looking things up on the Internet, going to the library, reading books, going in person to a place, and talking to someone who knows the topic well. Sometimes if you visit a place, you can take pictures or take a tour.
One thing to watch is how much research you’re doing. You want to do some, of course, but you don’t want to do so much of it that you forget to write the book. :)