Seven ways to Turn Telling into Showing
Flashbacks

One of the tempting ways to show backstory instead of telling it is through the use of flashbacks.
Although they dramatize the backstory, flashbacks still stop the main story and take the reader on a detour, so it’s important to keep them short.
Keep the flashback focused on one specific memory that’s triggered by something in the current scene (like a smell or old object).
Readers won’t appreciate a flashback interrupting an intense high-action scene. Instead place them inside the retrospective moments of a reaction scene.
For flashbacks to be effective, they should occur for characters the reader has gotten to know. Therefore, they shouldn’t be too early in the story.
Introspection

Introduce backstory by having a character muse about their world. As with flashbacks, their introspection should be triggered by an event in the current scene.
The reflection should be written in the character’s voice (not the author’s) and be full of opinions, reactions, and emotions about the things they think about.
Dialogue

Dialogue is perhaps the truest form of showing. It reveals what characters are expressing and allows the reader to observe and conclude the characters’ true goals and emotions.
However, be careful. Putting quotation marks around an infodump doesn’t turn it into effective showing. A character lecturing another can be just as boring as paragraphs of exposition.
Remove 'As you know Bob' Dialogue

Sometimes a character tells another something they already know. For example, “As you know, Bob, our company has been losing clients because of the outdated software we’re using.” Real people don’t speak like that.
The purpose of this approach is to inform the reader of something the characters all know.
In my opinion, this type of showing is lazy writing. It’s often seen on TV shows (where time is at a premium and they need to quickly introduce backstory).
Look for ways to reveal backstory through questions and answers (see below) or other ways of showing.
The example above could be replaced with dialogue:
Jane: “Ugh, just lost another client today.”
Bob: “Another one? That’s the third this month!”
Jane: “Yeah, they’re all complaining about our software being too outdated.”
Use the "Mr. Exposition Character" to Explain

The Mr. Exposition character is one who provides explanation to other characters (and to the readers), by virtue of their expertise or job. For example in police dramas, we have medical examiners and CSI techs who explain the specifics of crime scene to the investigators.
Instead of providing a long monologue or lectures, use the Mr. Exposition character to answer questions the other characters have. This approach allows the readers to learn along with the characters, and a dialogue breaks up the exposition.
Turn Mission Briefings into Dialogue

It’s not uncommon in war or heist stories to have a “mission briefing,” where a character describes the plan of attack. Strive to turn these potential lectures into dialogue so they aren’t an infodump. For example, characters could ask the leader questions. Participants might debate the strategy.
Use the "Watson Character" to Ask Questions

The Watson character is named after Dr. Watson who often asked Sherlock Holmes how Holmes arrive at some conclusion. The purpose of this character is to ask questions on behalf of the reader.
The Watson character works best when that character would naturally ask their questions (sidekick, an apprentice, etc.).
Sometimes the protagonist is a Watson character, such as in “fish out of water” stories, or when they enter a new world (Neo in the Matrix) or when they’re being trained (Luke Skywalker learning about the force).
Show, don't Tell (unless it's better to tell)
It’s important to remember that telling isn’t inherently bad. There are certain cases where it’s much more effective to tell. Recognize when you show and when you tell so that you can share information with your readers in a way that doesn’t stop the story.