When it rains, start typing.
Pause / Un-pause the game by pressing the Space key or by clicking on the screen.
If you enable Tips, you can get a peek of an upcoming word, but for a slightly reduced score.
Turn your speakers down a little! You can turn the sound on / off using the checkbox on the right.
Once you are past level 3, you can publish your scores anytime by clicking the 'Publish' button that will appear on the right.