Photoshop actions come in the .ATN file format and put simply,
actions are a series of steps that have been recorded by their creator.
This sequence of steps can then be reapplied at any time, which allows you
to recreate the end result without having to go through each individual step every time.
You can create or install different actions.
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To access your actions got to Window > Actions
You can load pre-made actions into PS.
To load an action you must:
MAKE AN ACTION, know all your steps PERFECTLY!!!
Click make new actions :
Label the action then hit record
Once you have hit record, every click you do will be part of the recording and the actions.
When you are done, click the stop button.