"Every story would be another story, and unrecognizable if it took up its characters and plot and happened somewhere else... Fiction depends for its life on place. Place is the crossroads of circumstance, the proving ground of, What happened? Who's here? Who's coming?..."
—Eudora Welty

Setting. A setting is usually the backdrop of a story. The place where the events and actions are taking place.
For example, in your average episode, our favourite ponies of the mane six are trotting around Ponyville. We’re so familiar with the town that we easily tune it out, turning our focus instead on the characters and their interactions, as well as the events and plot developments happening before our eyes.

Is that bad?
Not at all! In fact, normalcy in the backdrop of a world is one of the key requirements to a good story. Your story needs to be placed somewhere; the reader needs spatial references throughout the body of work. But how many? What should these references be? And how do you obtain them?

First, let us cover the ‘how’.
When your cursor enters a new location, a place that you deem worthy of having a little embellishment, stop for a few moments and think of exactly what it is you want to convey about that location.
Let’s say... an attic. What do you know about the average attic? Well, its walls are rough and are possibly made of bare wood. It smells faintly of mothballs, perhaps there’s a large chest filled with dingy passé-date clothes in a corner. Sound travels oddly on account of the low roof, coming out muffled and hollow. Are there motes of dust fluttering in the air, distorting the bright light as they poke through the holes in the ceiling? Are there windows with rafters? Or strange echoes coming up from a conversation below?
There, you have plenty of details about this room, just by thinking about it, and feeling it with your five senses (Protip: Using all five allows for a more dynamic and lively description).

But how much detail do you really need?

That all depends!
If you’re even moderately intelligent (which I hope you are) you’ll most likely guess that the amount of detail depends on the importance of a location.
Settings are a two-edged sword. Not enough is as bad as too much. When a character enters a room, and will only be there for three seconds, you don’t need to point out the location of each and every piece of furniture, the colour of the walls, the smell emanating from the pile of socks in the corner, or the sound of the computer’s fan overheating. You don’t need to know the name of the cat, the number of books on the bookshelf, the age of the computer, or the amount of days since the laundry’s been done.
Too much is tedious. You could have just said ‘Raven entered his messy bedroom, and came out with a broken knee’.

‘But, random guide that can’t really hear or respond to me, what do I say?’
The bare minimum! Or a lot. Again, it depends on the importance of the area or premise. Is this a central location to your story? Will characters return here multiple times, or will the way the room is arranged play a key role in events to come?
Once you know how important your location is to your plot, plan accordingly.

Onwards!
Generic entered the kitchen, his nose twitching as the scent of freshly baked muffins assaulted him. Taking a few steps forwards to one of the many counters, the unicorn levitated a piping hot cookie from a metallic trey and tossed it into his mouth, regretting it immediately as searing pain swept through his his mouth.
Was that effective? How much was actually told about the room?
-It smells of muffins.
-There are a lot of counters.
-Somepony’s been baking.

Is that enough for you to form a basic idea of the area? Yes, yes it is. Note that the things shown that build the location weren’t described that heavily. You don't need to spend hours constructing a three dimensional model with nothing but your keyboard for us, just find a few iconic items and describe those. The reader will form their own setting in the back of their mind.
On another note, this one on Chekhov's gun (more on that in another lesson) If any part of the location will be used, describe it as quickly as possible.

We don’t mean the floor or the walls. But the items that your character will use.

Does your character pick up a cookie? Where was it? In the fridge, on the table, in a tree (in case of cookie emergencies). These details don’t always come to the reader’s mind, but if there is a lack of context they will.

Generic was walking, moving forwards as he eyed the pile of homework that floated ahead of him. A few ponies passed by him, some smiling. But most were ignoring him. It was okay, he was used to that. Turning, the unicorn opened the door before reaching out and grabbing a cookie.

Where was Generic, and where in the name of Pinkie’s mane did that cookie come from? It’s confusing, and difficult to tie the movements of the character with any place.
Now, that’s the very basic principle behind the use for setting: having a place to see and imagine.
We’ll cover one last thing, a problem very common with new writers (we’ll cover this again in the future). Talking Heads. If there are two characters talking, no matter where they are, don’t just list of the pieces of dialogue continuously. Instead, break it up with some basic actions, actions that betray their reaction to the dialogue. Said actions can involve some interaction with the environment. (Lots of -tions).

Back to the very basics.
-To build a location, imagine it, then focus on the three or four most important elements. Use your six senses if need be. (Sight, Smell, Sound, Touch, Taste and Thought)
-Avoid going into too much detail. We, as the readers, don’t need to know every minute piece of information, just enough to create an image.
-Do give us details, or at least a passing mention, of any object that’s particular enough and that will be used.
-Pick when, where, and how much detail to give a location.

We sincerely hope that this was helpful in some way.
Keep scribbling, and you’ll be under the Raven’s eye.
-RavensDagger And The Good Folks Beneath The Raven's Eye.

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