Being the main character of the book, following Clarissa is an interesting path to choose.
Clarissa's section is divided into 2 parts, the present and the past. The present is relevant to the events that happen on this day in June while the past recalls all the flashbacks.
You can traverse through Clarissa by following only the Present links, by following only the Past links, or both the present and the past by following the Clarissa links.
Remember you can follow the written order of the book by following the Book links.