The Breadcrumb Question in Science Fiction

In a science fiction book, often the rules are just made up. And here you've invented several advanced technologies and so the reader is learning them as they go. How do you handle filling the reader in on the rules of your universe while also like leaving them enough breadcrumbs to follow? Isn't that a really difficult thing to balance? It could be. Like all of the things that are existing in the world are the hard part: explaining it to the readers.