Decide who your research target audience is. Will it be a group with roughly the same knowledge base about the topic you are presenting, or will it be to a group with very little knowledge about the topic? You will need to speak to their general knowledge level in order to hold their attention; this will determine what your presentation will look and sound like.
Identify the key points of your study. What is your thesis statement? The thesis statement should be one sentence that sums up the argument you are making. It should include a research question or statement of a problem. It should be strong, committed, and defensible.
Create an outline on paper about your topic based on the study you are referencing. The outline will be a rough draft of your presentation from which you will create your slides.
Break down the outline into the relevant sections of your study or project. Create these sections: an introduction which states your thesis, background information, the theoretical frameworks you are working from, analysis of the information, reasons why this analysis supports your thesis, a conclusion that postulates the potential ramifications of your argument and a reference page at the end.
Know exactly how much time you are allowed for your presentation, and don't exceed it. Don't spend too much time with prefaces. Get to your argument early in the presentation and keep referring to it throughout.
Create the slides in PowerPoint from your outline. Choose an attractive background for the slides, and insert relevant photos, images, tables or graphs. Don't make the graphics too busy or difficult to read -- keep them simple, to the point and relevant to your topic. Use language that is appropriate to your audience. Don't lose them with highly technical language they may not understand. Create text in bullet-point form with one or two sentences or phrases. Avoid using long quotations or text that will require too much reading.