Find the author’s books. Reading is the way into this author’s mind. Maybe she likes to detail battles between good and evil. Maybe he likes car chases in his thriller novels. You need to read them to understand them.
Understand the book. Just reading a book won’t do; you need to understand the author’s vision as well. Perhaps this writer likes his horror and goes into detail on the horrific tales of killers stalking teenagers. Your job is to ask why. What makes it so interesting? What themes does the author play with? Theme is crucial: it can be the basis for your thesis, as many authors explore the same themes over and over again.
Read more than one book. If you read his first book and find it terrible, don’t just give up on reading him. Explore other works to see if he is better. Look at it like a book review: you can’t say much about the author unless you know his complete works. So read as many books as possible. If you don’t like several, there is no need to finish them. Move on to the next author.
Request an interview. This isn’t a must-do step; often you can find plenty of information for a short article. However, if you really want to understand this author, an interview is the perfect place to do it. Ask as many questions as possible, trying to apply them to your thesis.
Write the portrait. Pull it all together and make it interesting. Speak to your readers from the outset. Be creative with what you are doing. Think of your market, too, because there are plenty of markets, online or in print, for this type of work.