Asking questions in Spanish is quite similar to asking questions in English. It's really just a matter of learning the vocabulary.
Here are the words to help you solve all the world's mysteries. (At least the mysteries in the Spanish-speaking world.)
The words in square brackets like [this] are optional. (More about that later!)
Just like in English, you can ask a question without using any question words. All you need to do is say it with a rising intonation at the end. (Consider the difference between saying, "He finished it." and saying "He finished it?")
You'll usually find that if the question includes one of those personal pronouns (you, me, he, she, they, etc) the question will make it move to after the verb, but either way is fine.
You might have noticed, there are a few differences between asking questions in English and asking questions in Spanish. These are the main differences between Spanish and English:
In Spanish you don't need to use words like "do" or "will" (auxiliary verbs). So there's no "will she come?", it's just "she comes?"
The important part is your intonation: Rise at the end of the question, so it doesn't sound like you're just affirming "yes, she comes."
As you saw in the examples above, in Spanish you can often leave the he / she / you / me (personal pronoun) out of the question. So instead of "You stole my iPod?" you'd just say "Stole my iPod?".
Of course this doesn't make much sense in English, but in Spanish each verb (like "to steal") changes to agree with the personal pronoun (he, she, they, etc).
So you can tell who it's talking about just by looking at the verb, and you don't actually need to say "you". There are a few exceptions to this, and you may need to clarify in some instances, but this is true a lot of the time.
In Spanish you'll put a verb immediately after the question word. So instead of "How do you know?" it would be more like "How know you?".
Or you could even just say "How know?" since the "you" isn't really necessary either.