There are some variations where more cards are dealt. The rest of game follows as normal.
If you don’t have a card to play, you must draw a card. If you draw a card that you can use, you may play it at this time. If you can’t use the card that you drew, play moves to the next player. [2] X Research source
The game ends once a player reaches 500 points and that player is declared the winner. [3] X Research source
If you have higher numbers in a different color than the one in play, try to change the color by playing a matching lower number in the color of your high cards. The one exception is the 0 card. There are only four 0 cards in each deck, so if you are trying to keep the color from being changed by your opponent, play a 0 to make it much harder for them to play the same number of a different color to change the color in play. [4] X Research source [5] X Research source
Remember you can change the color back to the one you have the most of by matching the same numbers of different colors. [6] X Research source
Make sure you don’t hold on to too many skip cards. Holding one or two can work in your favor, but stock piling them will add up to a lot of points if you’re caught with them. They are worth 20 points each. If you are playing two player UNO, you can use your skips right away because it gives you another turn automatically. Just be careful to end on a skip that you can match. You don’t want to have to draw cards because you can’t match the color. It is advise-able to use the odd number which you think is not with the opponent. So, he will withdraw a card and if he did not get the card, the next turn is yours. [8] X Research source [9] X Research source
If you are playing with two people, reverse cards act exactly like skip cards. In this instance, you can use the skip and reverse cards as early as you want. It’s a great way to quickly reduce the number of cards you have in your hand. Make sure you don’t hold on to too many reverse cards either. They are useful, but they are also worth 20 points each if you get caught with them. [10] X Research source [11] X Research source
Don’t stockpile these cards too much. They are worth 50 points each if you get stuck with them at the end of the round. [12] X Research source [13] X Research source
If you see the person that goes before you has only a few cards left, use a reverse and then a draw 2 or wild draw 4. Although they will be able to play one card, they will have to draw cards on their next turn, filling their hand back up and getting you closer to winning. If you want to stockpile a few of these to use at opportune times, try keeping draw 2s instead of wild draw 4s. If you are caught with a wild draw 4, it is worth 50 points, but the draw 2 is only worth 20. [14] X Research source [15] X Research source
