Make a list of all areas of gift decorating that come to your head. Don't censor yourself during this step. For example, include things like gift decorating in various customs, the psychological effects of gift decorating, preferred methods of gift decorating, specialists in gift decorating and other ideas.
Examine your list. Put a check next to the issues that interest you the most and evaluate them again. Pick one aspect of gift-decorating that you'd like to research and you think you could build thorough research about. For example, it might be easier to find information on cultural traditions and gift decor than psychological studies on people's reactions and expectations with gift decor.
Conduct your research visiting libraries, reading articles, studies, papers, newspapers and books on all aspects of your chosen subject.
Write down three or four possible arguments you could make about gift decor and circle the one that you think is the most debatable, yet the most supportable, in your research. For example, a statement like, "Well chosen gift decor makes recipients more excited about their gift," is weaker than, "Well chosen gift decor makes recipients like and appreciate their gift more." The first one is less arguable and people are less likely to disagree with it.
Reread your thesis statement. It should give the reader a sense of how you are going to argue this topic in gift decorating and point in the proper direction.