Clear the board by forming words from the letter cards. Any English word of at least two letters is a valid word. As in most word games, proper names, such as OHIO, are not allowed.
Tapping a card moves it to the letter tray. Once there's a valid word in the letter tray, a border appears around the word, and the large green submit button below the letter tray will become active. Tap it to submit that word, and remove those letter cards from play.
There is a meter in the top left corner of the screen that shows how many more cards you have to remove in order to beat the level.
Once you complete the level, you can move on to the next one, or you can replay it if you didn't get all three stars, or if you missed the Bonus Goal.