After you create a particle system, you can save it as a particle preset in the Particle Emitters, Favorites, or Favorites Menu folder of the Library, for future use. When you place particle systems in the Library, they become particle presets that can be used like any other particle preset.
Note: For organizational purposes, create a folder of your own in the Favorites or Favorites Menu category to store custom particle systems.
Open the Library and select the Particle Emitters, Favorites, or Favorites Menu category.
Drag the emitter you want to save into the stack at the bottom of the Library.
When you save a particle preset, it’s saved as a file in the /Users/username/Library/Application Support/Motion/Library/ folder (in the Particle Emitters or Favorites subfolder). Any custom objects that you used to create that particle system also appear here.
You can copy particle presets you create from this location to give to other Motion users, or you can place particle presets given to you in this same folder. When you copy a particle preset file, make sure that you also copy any graphics or movie files that it uses as well.
For more information on saving custom objects to the Library, see Adding Content to the Library.