Sigh...as a new writer, those words coming from your critique partners, beta readers, or even worse, your editor can be enough to drive you insane. As if deciding to write in the first place wasn't insane enough! Nevertheless...no matter what genre you write, it's true.
Having a problem understanding the difference between "Showing" vs. "Telling"? Let me see if I can explain it without anyone blowing a much needed brain cell.
Telling is basically taking a scene, and giving an overwhelming amount of information, such as too much back story (yes, if not written correctly, it can be overkill), or the lack of stimulating visual clues that force your reader to 'see' the scene or back drop of what the character is experiencing.
Showing is the opposite. Instead of telling a character's back story that leads up to a scene, that same information is given by way of dialogue. Another way would be instead of giving clinical descriptions about a location (there were large trees, or it was cold), describe it through the eyes of the character as they see it. What did it look like? (colors and textures) How did it feel (cold, hot, uncomfortable). Using the character's words (and the handy dandy thesaurus!), it will be much easier to make the change.
Let me give an example. This is from my original manuscript sent to my critique partners. This is a snippet from chapter five. In this version, you see the description I used (it's been crossed out because it was telling) and replaced by her suggestion which is showing.
I drew in a deep breath and held it for a few second in an effort not wanting her to know how much she was turned me on.