How can I achieve a professional-looking portrait with an out of focus background?

To achieve a professional-looking portrait with a blurred background, use a wide aperture setting (low f-stop number) on your camera to create a shallow depth of field. This will help to separate your subject from the background and create a pleasing bokeh effect. Additionally, position your subject a good distance away from the background and use a longer focal length lens if possible. Experiment with different angles and compositions to achieve the desired look.