You can use phrases like 'years later' or 'after a long time' to indicate a time skip. Also, describe changes in the characters or setting to make the passage of time clear.
Well, one idea could be a fanfic that explores the backstories of the main characters in Don Regular Show and how it shaped their present. Another could be a crossover fanfic where they interact with characters from another popular show.
You might come across fanfic that explores Don's backstory, revealing hidden aspects of his character. Or, there could be alternate universe tales where Don has different powers or a completely different life.
Small time skips in novels can serve several functions. For one, they can create a sense of passage of time without having to describe every single moment in between. This helps to move the plot forward more quickly. For example, if a character is starting a long journey, a small time skip can take the reader to the end of the journey without detailing all the days of travel. Another function is to build suspense. By skipping a short period, the author can leave the reader wondering what has happened during that time.
It depends on the genre and the audience. In some literary fiction, readers might be more accepting of complex time - related structures, including lots of time skips. But for younger audiences or in more straightforward genres like some action - adventure stories for kids, too many time skips could be a problem as they may have a harder time following the story.
You can do it by clearly marking the time jump and explaining the changes that happened during that period. Make it smooth and not too jarring for the readers.