1. Use CamelCase. You can type a word with SeveralCapitalLetters (or even type NewPage), which will automatically create a link to that page! A dashed underline means the page doesn't exist yet. Clicking on the link with a dashed underline will give you the opportunity to create the page. By the way, CamelCase is also known as "inter-caps."
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2. Use [brackets]. You can put [brackets] around any word to create a new page. For example, if you wanted a page named cars, you could just type [cars].