The final hurdle to jump in doing an Honors project is the qualifying oral examination. Much of the following holds as well for M.A. and Ph.D. level oral examinations. You presumably have already completed the data collection and analysis and have written a thesis that is (almost) acceptable to your advisor. Now you have to defend the project to your full honors committee. The committee is composed of your advisor, another member from the Psychology Department, and a member of another department on campus.
The first thing to keep in mind is that scheduling the defense means that the candidate is competent and should do well. Given a choice, the thesis advisor will not schedule an oral examination for a student who is not prepared or likely to do poorly. If problems arise and midway through the project it is clear that the student will not be able to complete the project, one option is to switch the honors registration to a directed readings or directed research project.
When the project has gone well, you write, think, reanalyze, and rewrite until your advisor agrees that it is in acceptable form to show to the rest of the committee. This is not yet the final-final draft; that waits until after the defense. Plan to give a copy of this version to everyone on the committee a reasonable time (a week or more) before the scheduled defense.
Before you start, expect to feel a bit nervous. This is how anyone would feel upon being evaluated. Presumably you are prepared and competent - at least your advisor has confidence that you will do well.
Once everyone is seated, you start by briefly summarizing your work. Even though the committee members have read your report, they want to hear you present a 10 to 15 minute abstract stating the basic question of the research, the main features of the method, the most important parts of the data analysis, and your conclusions, particularly those relating to your original question. Then your advisor will ask the committee members if they have any questions. Here is your chance to show that you know the topic and have given the project ample thought. Your responses should make it clear that you are interested in the topic and find the research worthwhile (no matter how it came out). Expect questions about future prospects for this research project. Do not worry if you draw a momentary blank on a simple question. You can say "I don't know." or "I can't recall right now." and return to it later. The questions continue, rotating through the committee. The committee often suggests fixing minor typos and unclear wording. Larger, more important, changes have to be reviewed either by entire committee or just by the advisor before the final draft is accepted.
When the committee runs out of questions and suggestions, your advisor will ask you to leave the room while they evaluate your performance. The first task of the committee is to decide if the report and defense are of honors quality. If so, then they have to decide if a High or Highest level is appropriate. Finally, you are invited back and the results are declared with exclamations of "congratulations!" and additional comments about your fine performance.