Pick something you do regularly and that might bother you or not.
Don’t overcomplicate it, and pick the first that comes to mind.
Now, ask yourself honestly, “Why do I do it?”
And don’t let yourself escape with shallow answers.
If the first response is shallow or unsatisfying, continue asking why on the response until you get to the roots.
Usually, you get a satisfactory response before five whys.
Now, you have found something you can work with.