Know the grounds for a yellow card
A referee issues a yellow card as a warning to a player. Two yellow cards result in a red card, after which that player must leave the game permanently. Reasons for yellow cards include:
Dangerous play. High kicking near a player?s head, for example. Illegal obstruction. This happens when a player intentionally takes a position between and an opponent when that player isn t within playing distance of the ball. Charging the goalkeeper in the goal area. Goalkeeper playing the ball with his hands when the ball is kicked by a teammate. Goalkeeper Infringements. Unsafe play such as charging the goalie. Goalkeeper taking more than four steps while controlling the ball. Intentionally wasting time at the end of a game.