Blue, "show vs. tell", like anything else, is a guideline for writing. I truly believe that much of this is intuitive to writing. If you've read good books you know a bit about how it's done. You can tell what works and what does not.
Do not feel bad for not knowing the names of these guidelines or beating yourself up for the use of them. With practice and reading, the intuitive part of being a creative writer takes care of many of these things.
I started writing when I was very young. I did not know there was such a guideline as "show vs. tell". I'd never heard of head-hopping. I had no idea in the world what deus ex machina was. The thing is, you don't have to know all of these things other than having a name for them, which is helpful in writing conversations. I imagine that if I had had all of this information about the *right way* to write a good novel, I never would have gotten started for having been overwhelmed by a million sticky notes all over my desk reminding me off all the things I needed to avoid.
When I joined AW, I learned most of these things; while I didn't know their names, they seemed to be intuitive in the writing anyway. I just got names for them. I took what I learned and put my already written (and now trunked) novel to task - how would it hold up to those things. I foot-faulted on some of them (in one thread I provided an example of where I head-hopped, for instance), but I learned from them.
But where I learned most about writing the novel wasn't in learning these guidelines, or the names of the *rules*;it was learned in the writing of the novel. The first one taught me how to go about writing the second one. Editing - which I learned a good deal of here - helped me more effectively edit the second one. Occasionally I will go through my already-written material during editing and keep an eye out for the guidelines and if I had followed them. I did not write the first drafts with those things in mind. I just wrote.
Reading is a great way to figure out what works in writing. If you read enough and write enough, the intuition of the craft takes over and your guidelines don't matter.
Don't bog yourself down in these details until you have your completed work to hold up to that light.
Give yourself permission to write CRAP the first time through, then use the guidelines to show you the way to fixing it.
Their names are not important, every guideline has an exception, and every plot device is doable if it is written well.
In first drafts sometimes I *tell* through scenes to get to the next, knowing I have to include it but if I'm not feeling it, I just tell it, then go back and fill in the showing when I have a clearer idea of what I need to happen there. Tell is a good placeholder for show. It holds the place for draft 2 (and sometimes continues to hold it until draft 13 when you finally have the show you need.)
I can see how I would work myself into a panic if someone had laid all the rules out to me before I ever started writing a novel. I would stifle the words trying to make them perfect the first time. I would not be able to get them written down as I attempted to stay within the yellow lines. sometimes you can't stay within the yellows. Sometimes you have hit the ditch, cut through a field and pray to the dirt gods you make it to the other side.
allow yourself to tell until you know what it is you need to show. That's what revisions and second drafts are for.