“Can you explain to me how this works?”

You've just started a new job in an office and you're trying to send a fax. You can't figure out how to use it. You ask a coworker:

Can you explain to me how this works?

explain to (someone) (embedded question)

When the topic being explained is just a short word, you use a different order:

Can you explain this word to me?

But when the topic needs a longer sentence, "to (someone)" goes first after "explain" like in the example above.

how (something happens)

This is an embedded question. Other examples of embedded questions:

explain how you knew that

explain what we're supposed to be doing

explain who you are