If you want to up your game and start thinking—and playing!—like a tournament player, make sure you're familiar with these lesser-known rules.
Scrabble rule: Tournament players use glossy tiles
The tilesets you buy at your local store likely have engraved letters, which aren't legal in tournament play. "Players could braille the letters or at least know when they are drawing a blank," says David Koenig, who has played tournament Scrabble since 2002 and is ranked in the top ten players in North America. Tournament-legal tiles have letters that can't be identified by touch, and players must hold the bag above eye level when drawing tiles. Besides Scrabble, these are the classic board games you should own.
Scrabble rule: Keep your rack balanced
"Most people mistakenly think a good vocabulary is needed," says Richard Silberg, who has been playing in Scrabble tournaments for decades. "Actually, the skill is trying to score well and balance your rack." Balancing means saving a mix of vowels and consonants on your rack that can help you score well on your next turn. Silberg gives this example: "If you have "ACKRSTU," you could play 'track,' 'truck,' or 'struck.'" His advice is to play "truck," as "the 'A' is much more desirable than the 'U', and keeping the 'S' is usually worth giving up a few points."
Scrabble rule: Know the difference between Double Challenge vs Dingle Challenge
Your opponent may challenge your word before the next play, and if it's found to be unacceptable, you take your tiles back and lose your turn. Under the Double Challenge in North America, Israel, and New Zealand, the challenger loses his turn if the word turns out to be valid. Scrabble games played elsewhere follow the Dingle Challenge rule: the first incorrect challenge is not penalized, but subsequent errors result in the challenger losing a turn.
13 Obscure Scrabble Rules Serious Players Need to Know, Source:https://www.rd.com/culture/obscure-scrabble-rules/