Presents are located under the Design tab. A present allows you to save you the Style Settings (Background, Colors, and Typography) of the applied design template. This allows you to quickly switch between different Style Settings of your website.
To save your settings as a preset, click 'Save New Preset'. Give your preset a title and then save. Your new preset will appear as an option in the dropdown menu.
The "Default" presets is the first preset your site was given. We recommend that you create a new Preset if you want to try customizing the Style Settings of the design template. This way, you can always jump back to the 'Default' present if you no longer want to keep those Style Settings you tried under the new saved preset.