One of my favorite parts of writing sci-fi/fantasy is worldbuilding. I love drawing maps, brainstorming magic systems, writing legends, determining technologies... It's like playing Civ, except I can't lose.
The hard part is figuring out how to relay this information to the reader. The most common (and wrong) method I see, both in my writing and others, is the infodump. Where the story just stops, and we have to read a page or two of the history of the Elven nation, or a treatise on the Foobarian language, or a detailed explanation of teleportation technology.
It's not our fault. Our favorite authors do it all the time. Like every chapter in Asimov's Foundation and Empire starts with an infodump, and don't even get me started on Tolkien.
Even so, we're told not to do it, or not to do it very much, or to do it in such a way that the reader doesn't realize we're doing it. How do we do that?
One way, I think, is to work with the reader strictly on a need-to-know basis. Don't tell them anything about the world except what they need to know to understand this part of the story. If the entire story takes place on a single planet, don't talk about the history of the Galactic Empire's colonization efforts. Don't describe the detailed rules of magic if the protagonist never has to think of them. Don't discuss the fishing habits of Tartarians just because the protagonist gets on a boat.
It's hard, I know. We spent all this time building this world, and we can't share it with the reader. Sorry, but it's true. The reader doesn't care about the details of our world. They care about the characters and the story. If they love them, then maybe they'll be interested in the world, but usually not the other way around.
It means some things will never be shared. Or maybe they'll only ever be shared in an appendix or on your blog. But it means the story will be shared, and isn't that the main thing?