UNO is a card game for two or more players. The object of the game is to rid your hand of all of your cards before the rest of the players. This is done by playing cards from your hand that match either the color or the value of the card on the table. UNO is simple to learn, but difficult to master -- unless you use the right strategies against your opponents.
Know Your Cards
The first step to mastering UNO is in mastering the deck. Each numbered card and face card appears twice in each color. Each zero card appears only once per color and there are only four wild cards and four "Draw Four" wild cards in each deck. Knowing how many cards are left will give you an advantage. For example, if you have two wild cards in your hand and one has already been played, you know there is still one left in play.
If a player has only one card left in his hand, he must shout "UNO!" or suffer a penalty. However, a player is only penalized if caught, so keep your eyes and ears open and dish out penalties when appropriate to keep other players from emptying their hands first. Likewise, a Wild Draw Four may only be used when no other options are available. If you call a player for improper Wild Draw Four use, he'll have to draw four cards himself as a penalty.
Like any competitive card game, watching the other players for certain tells can help you understand what they have in their hands. For example, a competitor may start playing fast and aggressively if she's holding powerful cards in her hand. Be aware of your own body language to prevent the other players from reading you. Likewise, you can bluff other players by drawing cards when you don't need them, making them think you have a weak hand when it's actually strong.
Know When to Play Cards
Hold on to your most powerful cards, such as Wild Draw Four and Reverse, and deploy them when the time is right. Cards that skip a player's turn or make them draw additional cards are best played against a player when he's close to winning, giving you the chance to catch up. However, you want to rid your hand of the most powerful cards before the end of the round or they'll add more value to your opponent's overall score if he wins the round.