Speed up when you want a moment to feel more intense, snappy, energetic, or even the obvious one, quick.

peed up when you want a moment to feel more intense, snappy, energetic

speed up moments of action, especially fights. Intense scenes, quick thinking, and arguments can work

Shorten - Shorten the chapter, scene, paragraphs, sentences, or even words. This makes the moment feel faster

Short Syllables - Use words that have few syllables. Choose the word "dance" over "promenade

Familiar > Unusual - Choose words and concepts that are more familiar or common to the audience. For example, choose "guess" instead of "hypothesize."

Simple > Complex - Similarly, choose words and concepts that are simpler. The more technical you get, the more the audience needs to slow down

The field that Steve stumbled upon was prodigiously verdigris with anthophilia circumnavigating every inflorescence.

vs.

The field that Steve stumbled upon was largely green with a love of flowers sailing around every floral arrangement.

Use More Telling - Telling is faster than showing . Tell what's happening when a quick pace is absolutely needed.

Slow down to create a more dramatic effect; to take time to be more serious, weighty, intellectual, technical, or leisurely; to give the audience important details; and to let them catch their breath

slowing down would be most effective by doing everything opposite of what it says above and some of that is true, but it depends on the situation

writing longer sentences will help slow a passage down, but if you simply do the opposite of everything listed above, you can easily run into The Purple Prose problem .

best way to slow down is to add more showing, details, and/or concepts.

like watching slow motion in a movie. The audience can see more detail. We get specific shots. Time itself seems to slow

Up to this point there has been fighting and action, and then something important happens, so it slows down and gets detailed.

It seemed to take Sirius an age to fall. His body curved in a graceful arc as he sank backward through the ragged veil hanging from the arch.

And Harry saw the look of mingled fear and surprise on his godfather's, wasted, once-handsome face as he fell through the ancient doorway and disappeared behind the veil, which fluttered for a moment as though in a high wind, then fell back into place.

Do not try to slow it down by repeating the same information the same way or even the exact same information in the same way.

slow down in a novel simply by the content of the scene. Two characters trying to figure out what just happened through a dialogue exchange will help the audience digest

something complicated the audience needs to understand, you may need to slow down, just a bit

The first duel has what I'll call an establishing, even pace. It explains to the audience how duels work, but in an even enough pace so that it doesn't feel like a boring

In the second duel , the pacing is quick and the duel itself is only about 20 seconds long (starting at 2:30)

The final duel is more important and dramatic, and it slows waaaaaay down. In fact, you get like an entire song as the bullet is coming toward Hamilton (notice this duel is about 4:30 minutes long).

if Miranda wrote that song and it really did just sing literally about a bullet coming closer to Hamilton, over and over, for an entire song. It doesn't work. It's boring

when the bullet is coming towards Hamilton, it becomes dramatic and significant because of all the culminating ideas, images, and concepts within that moment. It ties back to everything--his childhood, his family, his political journey, and perhaps most importantly the theme--how he will be remembered.

if you tried to slow that much down elsewhere, it might come across as melodramatic because it's more than the moment deserves. It hasn't gotten the same level of build up. It's not as important.