[subject] + 怎么 + [verb]?
怎么 asks how something is done. It goes in front of the verb.
A handful of 怎么 questions come up constantly: zěn me怎幺shuì说 "how do you say", zěn me怎幺dòu读 "how do you pronounce", zěn me怎幺zǒu走 "how do I get there", and zěn me bàn怎幺办 "what do we do".
With a tone of surprise, 怎么 asks how something came to be the case. wèi shén me为什幺 asks for a reason plainly; 怎么 says the speaker didn't expect it.
怎么 asks about method; zěn me yàng怎幺样 asks what something is like.