Final rendering:
1. Find a photo material that you want to use to create a bokeh effect, and then open it.
2. Next, create a new image. The shortcut key is CTRL+N. Set the width and height of the new image to 10 pixels, the resolution to 72 pixels/inch, and the 8-bit RGB color mode.
3. Fill the background layer with black. Our goal is to create a custom brush.
4. Execute Edit-Define Brush Preset on the menu bar and customize the name of the preset brush.
5. Return to the image where the photo material you just opened is located, then press the shortcut key F5 to open the brush preset panel, select the brush we just set, and then set it accordingly.
