Players take turns.
On your turn, you can either take one of the 'common' pieces and place it into your 'pit', play one or more pieces from your pit onto the board and score a word, or pass.
You choose one piece and move it into your pit. You can store up to five pieces in your pit. As pieces are taken, unchosen pieces will randomly improve. They may become orange 'rotatable' pieces, replace a letter with a purple blank, or gain red bonus-point chips. Each red chip under a piece is worth five points that are scored when that piece is taken.
Word creation and scoring is done as in the daily and live word-hunt games. If you haven't played them, it is suggested you start there (probably with the daily puzzle). Briefly, words can be made by connected letters, moving in any direction. Each letter can generally be used once and has a point value shown at the bottom-right of the tile. These basic rules are modified by the different bonuses on the board. There is a bonus for long words, starting at 25 points for an 8-letter word, and increasing by 25 points for each additional letter.
The word you score must use at least one letter from each of the pieces you placed, and at least one letter that was already on the board. The first pieces played must cover the yellow circle(s), if there are any.
Bonuses on the board are only scored once, the first time they are scored. If they are covered, but not used, they remain active until someone scores them by crossing them with a word.
If you can't or don't want to do anything else, you may pass. When all players pass consecutively, the game ends, and whoever has the most points is the winner.