Disclaimer:
When you speak about writing and how-to's, people tend to immediately contradict you, because in writing there is rarely the right way to do things or the only way to do things. Writing is a form of expression and we all express ourselves in different ways. So this is just a way I do it and it may or may not work for you.
Time-compressing transitions:
Most of our manuscript consists of scenes. A scene is immediate. In the scene, the events are shown as they unfold, in detail. Scene is the place for drama, action, declarations of love and hate, conflict and its resolution. Scene is where the fun is.
But some events take place off-camera, between the scenes. Time passes, changes take place, and we need to compress what happened and move on to the next scene. We have to summarize the boring bits.
So how does one summarize time? Sometimes weeks, months, even years have to pass in the course of the narrative. How do we work that in without boring the reader to death? After all, summarizing is basically telling, and nobody likes a lecture.
To compress time, you have to figure out what's important: the emotional change within your character. When we get up in the morning, we might be happy, but by afternoon we might be down in the dumps. Or the opposite: we could've started the day with a headache and finished it with a promotion. It's that change that's important. Not the time itself.
Time transition is like a tunnel: we see the character enter in one emotional state and emerge in another, ready to face the rest of the narrative.
Let's do a very simple example:
Mary Sue spent a sleepless night suffering from a migraine. In the morning, she showed up at the office determined to work but became too tired and left. We need to move Mary Sue:
Emotionally: from resigned to her fate to fed-up.
Physically: don't have to worry about it for the time being as our transition starts and ends at her work.
Temporarily: Morning to lunch.
As Mary Sue walked to her cubicle, the headache flared up, scratching at the back of her skull. Her head felt too heavy, her eyelids wanted to close, and an annoying hum filled her ears. By sheer willpower she forced herself to concentrate on the TPS reports, growing more and more annoyed with each new sheet of paper she discovered in her inbox. By lunch her headache had matured into a blinding migraine. Finally, she could stand it no longer and clocked out.
As long as you can hold on to your character's emotion, you can compress centuries and minutes with equal ease, transitioning your character five inches to the left of half across the galaxy.
Let's do a more challenging example:
Picklednose is a necromancer who is accompanying a prince on a voyage across a sea. He starts out feeling okay, but at the end of the voyage he is driven out of his skull and is very annoyed, because we need him to do something rash in the next scene.
We need to move Picklednose:
Emotionally: from apprehensive to annoyed to no end
Physically: from one coast to another
Temporarily: to two weeks later.
From the moment Picklenose stepped onto the wooden deck of La Bella, rolling and rocking with the pulse of the sea, he knew he would come to regret it. The ship was never still. It careened, vibrated, and listed, up and down, side to side, like some drunken whore at the end of the night. The cold spray dampened his clothes and his sheets, until he no longer remember what it was like to be dry. But the salt, the salt was worst of all. The bitter, sharp salt of the sea was everywhere: it spoiled his food, it caked in his hair, it formed a grainy layer on his skin and made his eyes water. And to add insult to his misery, Prince Charming loved it all. He practically bounded out of his bunk to scurry up the mast or to pull on some damn rope, reveling in grunt work with infuriating enthusiasm.
By the time La Bella finally pulled into port, Picklenose was sure of two things: first, he hated the sea and the sea returned his hate and second, Prince Charming was completely and hopelessly daft.
All of the transitions we've used here are very clearly defined as transitions. But actual written narrative is more subtle and fluid. There transitions mutate and take all sorts of shape. They are disguised, they are presented with subtlety and a lot of times you don't even notice they exist.
Here is an example from Nora Roberts.
When one of the most famous faces on the planet was beaten to a bloody, splintered pulp, it was news. Even in New York City. When the owner of that famous face punctured several vital organs of the batterer with a fillet knife, it was not only news, it was work.
Getting an interview with the woman who owned the face that had launched a thousand consumer products was a goddamn battle.
Nora Roberts writing as J.D. Robb, Origin in Death
Elegant, isn't it? The character is never mentioned, but you know what is going on in her head: first, she heard about crime, then she realized she was assigned to the murder, and now she is frustrated because she obviously tried to interview the victim of the battering several times, and got nowhere. And none of this is directly mentioned, but we know it anyway.
That's why Nora Roberts sells my entire print run in a week, in hard cover.
Hope it helps. :)