This is a dilemma that people are having a lot lately and I think it is mostly misled. For starters, as a writer, I physically cannot give you any information unless I tell you something. I only have my words, and words can only tell you things. What most critics mean when they say "show, don't tell" is really, "tell me different things" or, "tell it to me without interrupting the story."
This is something that I was taught: language that insinuates motion or change is a hallmark of showing. Any word that acts as an '=' sign is usually telling
For example rather than:
It was sundown.
You could write
The surrounding shadows stretched out slowly as the sun sunk back down over the horizon.
In the first sentence, it is just two words connected by an '=' sign: "It = sundown." Whatever was just happening was abruptly put on hold so you could fill the reader in.
In the second sentence, things are happening. The sun and shadows are moving. 723
Yes, you are telling the reader some things: that the shadows are getting longer in length and the sun is going down, but the difference is that these details add to the action of the scene, as opposed to stopping everything to tell the reader "it was sundown." This shadowy, dusk scene can add tension or highlight the passage of time for the main character, etc. It adds to the action. It doesn't stop it altogether.
So a useful exercise could be just that: changing '=' signs to more active language, or seeing how many different ways in which you could say the same thing. You could, for just the "it was sundown" example, also write:
The sky turned all shades of turquoise, gold, and pink before settling back into the ultramarine shade of nighttime in Alaska.
Or,
A hush fell over the desert, and the air grew crisp while night washed over the frontier
among thousands of other things. Stretching your imagination in this way can help your style, your descriptive language, even your storytelling immensely. It is also fun.
It goes for characterization, too. Rather than tell everyone your antagonist is upset, make her throw things, make faces, do things that someone who is upset would do.
Hope this helps. 723