While in Tagging Mode, you may create new metadata presets by tapping on the New Preset button:
Tapping on the New Preset button will slide out the New Preset Drawer:
At the top of the New Presets Drawer, type the name of your new preset. Below that, enter the metadata you want to associate with each respective metadata field.
The checkbox to the right of each metadata field toggles if that specific field will be applied when you apply the preset. Note that if a field with a checkbox contains no text, the blank/null will overwrite any existing information when the preset is applied. Any existing metadata applied to a photo will be intelligently merged with the preset if a specific field which doesn’t have a checkbox.
To delete a metadata preset, tap the Remove Preset button at the bottom of the preset drawer. Removing a preset will not remove the metadata previously applied to photos.