You can improve your score by using the bonus tiles as much as you can. Try to swipe as many words as you can with the bonus tiles included. The TW (triple word value, red color) and DW (double word value, yellow color) are the most valuable bonus tiles. Additionally, there is TL (triple letter value, blue color) and DL (double letter value, green color) bonus tiles which will can also help you score higher in the game.
The length of the word can also increase your score, the longer the word the higher the score. You can also increase your score by earning Ruzzle Length Points. A longer word means more length points, for example, a 9-letter word will give you 25 Ruzzle Length Points, but a word with 4 letters or less will give you zero extra points.