Aquamarine Picture Style is a custom, downloadable preset for Canon cameras
I understand you're looking for an article or guide on how to download or apply the (likely one of Canon's pre-installed or downloadable Picture Styles, similar to "Autumn Hues," "Clear," etc.).
Download the Canon EOS Utility software, connect your camera via USB, and use the "Register Picture Style File" feature to upload it to a user-defined setting (User Def. 1, 2, or 3).
: Click OK to save the style to your camera. It will now appear in your camera's Picture Style menu for use. Picture Styles - Canon Europe