Hey all! Here's another cheat sheet. You can read the full article about interior monologue here. However, I did not cover the two less common ways to show characters' thoughts in that article: soliloquy and stream of consciousness. I'll dive into them in an episode of my upcoming podcast The Writer's Guide to the Galaxy, which will be launching in the next few weeks, but for now, here's a quick and dirty explanation:
Soliloquy is generally only used in plays. It is where a character speaks his thoughts aloud so the audience may hear them. E.g., Hamlet's famous "To be or not to be..." speech.
Stream of consciousness is really just a different type of interior monologue. You can think of it like unrefined and unfiltered consciousness as compared to the refinement and filtering that goes into crafting the more normal interior monologue.
And that's all for now, see you next week for Characterization!