1. Open Apple Aperture
2. Select an image
3. Right click (control-click) on the image
4. The contextual menu will appear, select Edit With
5. Select PhotoFrame
6. The PhotoFrame for Aperture dialog will appear, press the Open... button.
7. Your image will open in PhotFrame where you can select the frame or design elements you desire and adjust them.
8. Press the Apply button in PhotoFrame to apply the results and return to Aperture.

For Details on using the PhotoFrame for Aperture dialog look below. 

• Search: Type in the name of a preset or favorite frame. The results will appear in the Search Results category. 
• Category List: Lists your preset categories as well as a special category for your Favorites. Click on the triangle to open each category, just like the Library in PhotoFrame.
• Description: Displays the description for the selected preset. You can close this section by clicking on the triangle next to the section title.
• Cancel: Cancels PhotoFrame for Lightroom
• Open...: Rather than applying a preset directly, this option will open your image in PhotoFrame so you can manually select the frame(s) and options
• Apply Preset: Applies the selected preset to your image(s)

Note: Aperture will always create a copy of your image for editing. You can control the file type and options that it creates in the Aperture preferences.