Some things don't need a lot of explaining. Really, you can trust your readers to understand a lot of things, even if they're different from the way they are in our real world without additional explanation.
A few examples:
1. There are famous journals, artists, and magazines referenced in "Damsel in The Red Dress" that don't actually exist, but no extra explanation is needed.
2. In "Hushabye Prince" there are (going to be) TV shows referenced that again, don't exist.
World building is important as much as it pertains to the way your characters interact with the world around them. If there are weird creatures, mention them only if the characters are going to have some connection with them, be that fighting them, training them, or wearing a suit of armor made of their indestructible scales.
If the world is set up strangely, or has strange vehicles, again it's really only worth noting in as much as it pertains to the story. You want to make the world bigger than the plot, so little details about the world they are moving through are worth noting, but a lot of time spent discussing things without relevance isn't worth doing unless it will have relevance later. This is especially important for fantasy stories, because people aren't going to WANT to spend forever learning how the government of a society works unless it relates to the plot somehow. You may want to bring in NEW characters to make it a more long running story (like say "Lord of the Rings") with multiple story lines in the same world. But if that's your idea, even those details you add to make it a full world, should probably have relevance in at least one of the story lines you're planning. Basically, don't just add extraneous information for no reason, good writing is about EVERYTHING having a purpose.