Measure duplication
Two E tiles can be useful; four usually restrict the rack. Repeated letters reduce the number of distinct arrangements, especially repeated high-friction consonants. When choosing between similar scores, prefer the play that removes harmful duplication.
Keep complementary groups
Do not judge tiles one by one. ING, ER, and ST are useful groups because they connect to many roots; an isolated V may need a nearby vowel. A good leave is a small system whose letters work together.
Use the unseen pool
Late in the game, track what remains. Holding Q is different when both U tiles are unseen than when they are already on the board. Exact tracking is essential in serious play, while casual players can still benefit from noting premium letters and vowel scarcity.
Know when to exchange
Exchange when the rack has low scoring potential, poor balance, and no board rescue—and when enough tiles remain in the bag. Do not exchange simply because no long word appears; a short positional move may repair the rack while scoring.
Quick review
The strongest habit is to separate hard constraints—letter counts, length, fixed positions—from helpful clues such as frequency and familiar patterns. Use the tool to narrow possibilities, then use meaning and context to choose.