The following advice on playing Spades was contributed by Szu Kay Wong. It mostly applies to the three player game. Some suggestions for the four player game are also given.
Your job is to try to guess exactly the number of tricks you will win. Usually, you will bet all your aces and kings, and frequently, your queens. Jacks are sometimes bet, usually number cards are not bet. Spades are higher than all other cards of other suits, so numbered spades are sometimes bet. The number of tricks bet also depends on the number of cards of one suit.
In the four player game, Jacks fall in the same category as number cards: you should never bet them. Queens become more risky, as do kings. However, remember that even though one player may have only one of a suit you have a king in, he might be your partner. The same applies to queens.
Unless I have very few spades (3 or fewer), I bet all spades 10 or higher. If I have very few (2 or fewer) of a given suit, I might bet a nine or eight or seven of spades, and use it to trump another card.
Don't forget! Ace of Spades is automatic. King of Spades is automatic if you have the Ace, and so on.
If you are very behind, and a player is close to winning, then you will usually go blind (bet without looking at your cards) to gain double the points. You have everything to gain, and if you lose, you would probably have lost anyway.
Here's the normal (well, at least when I play) flow of the game.
On the first trick, the ace of clubs is usually played, so that player takes the first trick. This can't happen if a player has the 2 and the ace, since he has to lead the 2, and can't play the ace. The player taking the first trick usually leads another ace, since they can't be beaten unless a player is completely out of that suit. If a player is out of aces, he usually leads a king of a suit of which the ace has been played. If no aces or kings, a queen of a suit which the king and ace have been played. However, at this point, all players have played two of that suit, and chances of a player running out increase.
In short, player plays the highest card of a given suit remaining.
If a player has none of the "highest remaining cards", he usually tries one of the following.
Spades: When a player runs out of a given suit, usually the player plays a spade. If two players run out at the same time, both may play a spade, and the highest one wins.
I usually try to save the Ace of Spades (the most glorious card in the deck, since it may never be beaten) until the end of the game. If you only need one trick to make your bet, and you have the Ace of Spades, dump every trick possible until the end, then hold up your Ace at the end and smile. This will not work in the following cases:
If you have the King and Ace of spades together, then do the same, expect a first "force" you give up the King, then the Ace on a second "force".
In the four player game, the play is the same, except that if your partner is winning a trick, and you run out of the suit led, you usually dump so your partner keeps the trick. If you take it, your partner loses a trick, which means you as a team lose a trick. If a team works together, then when this happens, your partner, knowing you have no more of that suit, will play it. Then, you jump a spade and take it.
At the end of the game, if you only need one trick, your partner is winning the trick, and you have the Ace, you would play the Ace to beat your partner, so you as a team will refuse the trick and not get a sandbag.
This is an alternative strategy. In this plan, rather than taking the number of tricks you bet, take as many tricks as possible so that someone else cannot get their number, and then loses 10 times their bet. Most of the time this is used as a defensive strategy, i.e. another player has a huge lead or is close to winning the game, and you are forced to try to stop them. This strategy hinders yourself from scoring, since it means taking bags and reducing your score, and should therefore be used with caution. Remember, if you miss the cut, you take a ton of bags, and your opponents get the maximum score possible, when just playing normally would have given you the maximum score possible, and they would get the bags.
Cutting is a legitimate tactic if you are behind. If you try cutting when you have a 200 point lead and you fail, you are stupid. If you succeed, you are a jerk that should be banned from ever playing Spades.
Q: Should I always play the highest of a suit?
A: Usually. Ther are some exceptions. It is a big advantage to play last in any given trick. Then you can see all the cards played and play appropriately. If the other two players play a 2 and 3 of clubs, of course, you win if you play the 4. However, I recommend never taking a trick with a numbered non-spade, since they usually go towards bags.
Possible tricks:
Queen-Ace combo: If you have these two without the King, if you come up last in the trick, you can play the Queen, then lead the Ace. This gives you the first two tricks, and forces the King to go another round, and possibly get trumped.
Others are Jack-Ace and Jack-King (if Ace has been played)
Q: When the highest of a given suit has been played, what do I play?
A: Middle cards (eights, nines, tens) are usually dangerous. They can't be counted on to take tricks, but they sometimes take bags at the end of the game. If most of the tricks you bet are Kings and/or Aces, you should dump these middle cards (8-9-10) first, then lower cards. If you bet on a few queens or jacks, those middle cards could be insurance, and you might want to keep them.
Q: In trumping, couldn't I play the 2 of spades, or another low one?
A: Yes. However, lower spades are also useful in "flooding spades". You can use these later on. Lead a low spade might force another player to play a higher spade (even the Ace). The best spades to use to trump are again the "middle" - 8,9,10 of spades.
Q: You say always lead high non spades early, but save high spades late. Why?
A: Remember, high non-spades can be trumped. If you play the Ace of hearts on the first round of hearts, it likely won't be beaten. But, if you play it on the fourth round of hearts, it likely will. However, high spades can't be trumped. Keeping the Ace of Spades will
give you control of the game. You always know you can play it and take a trick whenever you want. If you play it, you give up control to the King of Spades, then Queen, etc. If you have the King of Spades, but not the Ace, you are probably trying to force the player with the Ace to play it early, then you can wait to play your King. You flood spades by leading low spades, hoping the player with the Ace has only that spade left and must play it. Or, if the player needs no more tricks, they might play the Ace just to "get rid of it".
Take your tricks early, and take tricks with only the cards you intend to. taking extra tricks usually result in bags. However, if someone trumped your king of diamonds, you better win another trick.
If you don't have the Ace of Spades, but have the King and/or Queen, try to force the player with the Ace to play it. Usually, you flood spades with low (2's or 3's) to force out higher. If you play a higher spade (5, 6, or 7), others may play lower spades, and you take a bag. The point behind flooding spades is that if you lead a spade, all players lose one spade if they have one.
Grab the Queen and/or King when you can. If the other two players led spades, it is a good time to play the Queen and/or King (if that will win the trick). If you have a lot of spades, however, try to wait until the end, since the Ace will likely be forced out before your King will.
When you have all your tricks, or are missing one with the Ace of Spades in hand, dump every trick if possible. If you have to take a spade trick, take it with your highest spade to cut damage.
You bet blind (bet without looking at cards) when you are far behind and/or another player is close to winning. The best time to go blind is during a game you bet last, since you have an idea how good or bad the other hands are.
For three player, remember that there is one card missing. If that card is low, it usually doesn't affect the game. If it is high, it does. If the trick comes to you, the ace hasn't been played, and you have the King, or Queen (if ace and/or king haven't been played), play your King or Queen, since, possibly, the higher card is missing.
Once in a while, the Ace of Spades is missing. This really messes up the game, since three guys scramble to win their high spades to protect them from the Ace, and the Ace isn't even in.
My list of phrases and facial expressions for the game.
If you can hold on to the Ace (or King or Queen) until the end, and it is the last card you need, hold it up in front of you, and smile at your opponents.