In a first draft, we often write things as they occur to us. Maybe some dialogue first, an occasional gesture or action by one of the characters, throw in an emotion or two. The result might be something like this (for the purpose of illustration, I have hacked this passage from Leviathan by Scott Westerfeld):
"How long can we last without parts, Klopp?" Alek asked.
"Until someone lands a shell on us, young master."
"Until something breaks, you mean," Volger said.
Klopp shrugged. "A Cyklop Stormwalker is meant to be part of an army. We have no supply train, no tankers, no repair team."
Alek shifted the cans of kerosene in his grip. He felt like some vagabond carrying everything he owned.
A functional scene, but confusing for anyone other than the author. The reader only knows what you tell them, and the lines above don't say much by themselves.
Grounding a scene means imagining that you are painting a picture in the reader's head (because you basically are). Without any additional context, the reader has nothing in their mind, a white space with only the characters and objects you place in it as you name them.
By the end of the first line above, the reader knows there are two characters: Klopp and Alek. They might know something about these characters from previous scenes, but they don't know where the characters are or what they're doing now. All they have to imagine are two characters they know standing in empty space.
The third line adds another character: Volger. The reader now has to reimagine the scene, possibly even replaying the first two lines in their head to imagine Volger also being present. This slows the reader down as they have to rethink what they thought they knew.
The fourth line mentions a Cyklop Stormwalker, some kind of vehicle. Are they in this vehicle? Are they repairing it? Who knows? Not the reader, but they have to revise their mental image again. Finally, in the last paragraph, we get some visual. We know that Alek is carrying cans of kerosene, so maybe they're carrying these back to the Stormwalker, but where are they now? The author might know, but the reader doesn't
The most straightforward way to fix this is to ground the reader in the scene. Start the scene with a description that answers the questions: Who is here? Where is here? What are they doing?
For example in the passage above, we could add the following paragraph before the dialogue:
Alek, Klopp, and Volger trudged along the streambed, the kerosene sloshing with every step, its fumes burning Alek's lungs. With each of them carrying two heavy cans, the trip back to the Stormwalker already seemed much farther than the walk to town this morning.
With just a couple of sentences, we now know who is in the scene (Alek, Klopp, and Volger), where the scene is (along a streambed), and what they are doing (carrying kerosene back to the Stormwalker). This simple addition makes it far easier for the reader to visualize the scene, and they don't have to revise that mental image with each new line of dialogue.
But what if the reader stopped reading at the last chapter and hasn't picked the book back up in months? Or what if they were distracted when reading the last chapter? Or what if they just don't remember the details—or at least the important details—of what happened in the previous scene? It is often useful to drop a hint of where this scene occurs in the plot as well as in time and space, something like this:
And yet, thanks to Alek, they'd left behind most of what they needed.
This serves as a quick, clean reminder without needing to do a full recap. The reader knows something bad happened, and the line above will be enough to remind most readers what that thing was.
It also has the added benefit of implying what Alek feels in this scene, which is in some ways even more important.
Let's put it all together and add a little bit more of Alek's emotions to the scene (i.e., let me show you the full passage that I hacked apart for illustration):
Alek, Klopp, and Volger trudged along the streambed, the kerosene sloshing with every step, its fumes burning Alek's lungs. With each of them carrying two heavy cans, the trip back to the Stormwalker already seemed much farther than the walk to town this morning.
And yet, thanks to Alek, they'd left behind most of what they needed.
"How long can we last without parts, Klopp?" he asked.
"Until someone lands a shell on us, young master."
"Until something breaks, you mean," Volger said.
Klopp shrugged. "A Cyklop Stormwalker is meant to be part of an army. We have no supply train, no tankers, no repair team."
"Horses would have been better," Volger muttered.
Alek shifted the burden in his grip, the smell of kerosene mixing with the smoked sausages that hung around his neck. His pockets were stuffed with newspapers and fresh fruit. He felt like some vagabond carrying everything he owned.
"Master Klopp?" he said. "While the walker's still in fighting prime, why don't we take what we need?"
Now we have a scene that can be easily visualized, that doesn't require mental revision as the reader reads each new line, that reminds us what the characters are trying to accomplish, and that shows the character's emotions. In other words, we have a well-grounded scene.
Should this be what was written in the first draft? I mean, only if you already have a clear, clear idea of the scene from the start. For most of us, the first draft is essentially our pencil sketch of the story. Revision is where we make it read well, like I've done above.
I can't say that this is how Scott Westerfeld actually put this scene together, but it's how most of my scenes get put together and probably most of yours. Write what comes to mind first, then go back and make it look like you knew what you were doing all along.
