Summarize this article in one sentence.
Some tournaments are run using basic checkers rules, referred to as Go As You Please, GAYP, or freestyle. Others follow the 3-move rules, which limit players' options at the start of the game to a set of three move sequences. (The 3-move rules greatly reduce the possibility of a draw between skilled players.) More recent books will contain up-to-date strategic advances, but this is less important if you're a beginner. Browsing the checkers shelf at a library or bookstore can help you find a book that is helpful and fun to read. Playing against more experienced players who are willing to share their knowledge is a great way to improve your game. Whether that means entering tournaments or finding your local amateur expert, the better your opponents are, the more you'll learn.

Summary:
Decide which rules of checkers to follow. Study a checkers strategy guide that matches your rules system and skill level. Play against the best opponents you can find.