How to outline an obect easily

Like JJ said, we need to know what you're trying to select so we can make suggestions. Anything complex would be best suited with a pixel mask. (e.g., Mostly organic things, like people or pets.) Anything simpler or with a hard edge (e.g., A ball or the edges of a table) would be best suited with a vector mask. Both are non-destructive but require different workflows.

You need to post and example of what you want to outline. And how you want to outline.  You are not going the be able to automate outlining a detail photo. Photoshop's  auto select features are designed to select object  to isolate them not outline anything.  You can stroke selection convert selections to path and stroke paths with some tools.  The new versions of  Photoshop has a trace pen but I be .... if a can use it well.     What are you trying to outline.