Myself is a pronoun you use when you're both doing something and receiving the action of that something. When you say “I taught myself to juggle,” you're explaining that you were both the teacher and the student. When you accidentally bonk yourself on the head, you're both the bonker and the bonked.

The word works like a mirror in a sentence. It reflects back to “I” and shows that the person doing the action and the person affected by it are the same. “I made myself a sandwich” means you both made it and ate it. “I saw myself in the window” means you caught your own reflection.

People also use myself for emphasis, to draw attention to who's doing something: “I built this treehouse myself” makes it clear that you did the work, not your dad or a carpenter. This emphasizes your independence and accomplishment.

Sometimes people incorrectly use myself when they should just say “me” or “I,” thinking it sounds more polite or formal. They might say “The teacher gave the assignment to John and myself,” when “to John and me” is actually correct. An easy test: remove the other person from the sentence. You'd say “The teacher gave the assignment to me,” not “to myself,” so “me” is right when John's there too.