Revealing Clues

When crafting a story I have to find a way to let my characters learn certain facts that will lead them to the next step towards their goal.  There are several ways to reveal clues.  Sometimes I stumble upon these methods in the process of writing and sometimes they are something I plan into the story.

Objects - finding a photo, a keepsake, or a written record such as a newspaper article or a journal

A Boastful Character - usually the antagonist or an associate of the antagonist brags about their plans

A Guiding Character - someone in authority or with more experience gives the protagonist an idea about where to look next

An Event - A celebration, a storm, or even a death may show the protagonist something important