Important VIM tip that cheatsheets never mention for some reason: text objects. First, remember these two things: a for a, and i for 'inner'. 'daw' deletes a word under the cursor. 'diw' deletes the contents of a word (the 'inner' of a word) under the cursor.

What? How is that useful?

'das' deletes a sentence under the cursor. 'dap' deletes a paragraph under the cursor.

'da{' deletes the block of text that's currently surrounded by braces. 'ci(' deletes the inner content that's surrounded by parentheses and puts you in insert mode. 'gqap' reformats the contents of the paragraph under the cursor ('gqip' will end up leaving your cursor at the beginning of the paragraph instead of the end.)