Build your background by reading broadly about your object.
Note: These are not the types of sources that Dr. Clemente has asked you to cite, but building your background with these sources can make your later searches more effective.
As you read books and articles about your object, look for the primary sources that the author's refer to: historical magazines and newspapers, letters, diaries, etc. If you see something that looks promising for your project, ask Mark for help tracking it down.
We also have several databases that give you access to primary sources related to fashion. Here are some best bets.