For personal reference, and general information on what the Cards do.
Wand summoning:
"Key that hides the power of the star, show your true nature to me. As your master, I, Sakura, command you -- Release!"
Sakura Cards
1. 闇 The Dark
The Dark (闇) is able to warp space, creating darkness that can isolate and nullify non-magical beings if given enough time (like Erase). Dark is the first card under Yue and is special in that it cannot be physically attacked.
Dark's visible form is a regal woman draped in black with straight ebony hair. On its Card, it clutches a crescent moon in one hand, and a star in the other.
2. 地 The Earthy
The Earthy (地) is capable of considerable property destruction by creating earthquakes and various other geological disturbances. As one of the four elementals and the last card to be captured in both manga and anime, it is perhaps the most powerful of the Clow Cards. However, in accordance with the Chinese balance of five elements, it is vulnerable to Wood.
Earthy's visible form is a giant serpentine pile of earth and rock. In the manga it appears as the woman depicted on the Card. It is directly linked to Cerberus.
3. 消 The Erase
The Erase (消) has the power to make almost anything, including people, disappear. Erase also has the power to erase magical elements, once banishing a pit full of stuffed sheep created by Eriol during one of Sakura's trials. Once something has been erased by Erase it can be returned if the card is captured but, if that person or object is gone for too long, it disappears permanently.
Erase often appears as a bank of grayish fog, but its visible form is a small imp dressed in a yellow-and-white-patterned court jesters outfit. It has a large ruff around its neck with a long hat with two points that trail almost to the ground. On the Card, it carries a cape posed as if to hide something -- similar to how magicians use capes during a magic trick.
4. 火 The Firey
One of the four elements of magic. The elemental cards are considered second in power to Light and Dark. All the elemental cards will have their respective magic (In this case, the power of fire), but they can also behave like an elemental creature.
The Firey resembles an angel covered with flames. It is directly linked to Cerberus.
5. 花 The Flower
The Flower (花) has a gentle and fun loving spirit, able to create any kind of flower or blossom. However, she sometimes does this a little too enthusiastically, once nearly burying Sakura's school underneath a mountain of flower petals. Though Flower has no offensive capability, Sakura has used it to create bouquets and blossoms as presents for others. In the manga, Flower has been used defensively to create a shield of blossoms around Sakura.
Flower's visible form is a young lady in a long flowing pink dress, with corkscrew pigtails and a flower pattern on her forehead. On its card, it appears to be holding a large blossom.
6. 翔 The Fly
After its transformation into a Sakura Card, Sakura is able to use Fly's wings herself (they grow out of her back), allowing her to keep the sealing wand free to use with other cards.
Fly resembles a giant white bird with a long neck and short beak.
7. 灯 The Glow
The Glow (灯) is one of the harmless cards, as its only power is the ability to create hundreds of tiny glowing orbs that resemble fireflies.
When enacting its power, Glow casts off hundreds of tiny softly glowing green orbs that float down slowly to the ground like flower petals. In its visible form, it resembles a tiny fairy.
8. 幻 The Illusion
The Illusion (幻) is an aggressive card (reasons for this behavior are unknown) capable of creating an illusion based on whatever the viewer expects to see or wants to see. This means that each person will see something different when viewing the illusion unless they are all thinking of the same thing at the same time. Usually this illusion takes the form of whatever the person is most afraid of, though it has been known to take the form of whatever is most significant in a person's mind at the time.
Illusion can change its form based on what the watcher expects to see, but while transitioning between forms, it resembles a kaleidoscope pattern.
9. 跳 The Jump
When summoned Jump appears as pair of wings on Sakura's ankles and allows her not only to jump great distances but also to land safely from falls that would otherwise kill her. In the anime Jump appears to have a number of other powers, including the ability to possess inanimate objects, allowing them to jump, as well as the ability to merge many smaller objects into a larger version of itself. Sakura never uses these additional powers, though, and they are never demonstrated in the manga.
In its visible form, Jump resembles a rather strange looking stuffed pink rabbit with long floppy ears, in its card form The Jump has a pair of wings.
10. 光 The Light
The Light (光) is able to bring light to any area, also able to turn night into day. Light is the first card under Keroberos. Light and Dark are always together and the two most loyal cards, making them the most difficult for Sakura to transform into Sakura cards.
Light's visible form is a regal woman draped in white with white flowing hair. Its Card form clutches a sun in one hand, and a cloud in the other.
11. 迷 The Maze
The Maze (迷) is able to create pocket dimensions inside the real world, which contain giant mazes. Unlike conventional mazes, which work in three dimensions, the puzzles created by Maze are twisted through four or more dimensions, allowing people to walk upside-down, up staircases that cannot really exist, and generally to become lost in a world that defies the laws of perspective.
Maze also prevents any kind of "cheating" by raising walls to stop people from climbing over them and by repairing walls that have been damaged by people trying to break through.
Maze is invisible from the outside, but from the inside it resembles a multi-dimensional green maze with upside-down staircases and impossible perspectives similar to those drawn by M. C. Escher.
12. 鏡 The Mirror
The Mirror (鏡) is able to copy people like a reflection in a mirror and (literally) become that person. It is also capable of becoming a mirror and reflecting objects. Mirror appears to be troublesome and mischievous, but it really is a frightened and lost spirit. Mirror is the most human of the cards, as its ability to duplicate an identical copy of its (usually human) target also allows it to speak and express emotions.
Mirror's visible form resembles a beautiful green-haired girl, draped in a long flowing kimono holding a mirror in her hands. On some occasions, Mirror just appears as the mirror that she carries, useful for reflecting images and deflecting magical attacks.
13. 影 The Shadow
The Shadow (影) is a mysterious card able to manipulate shadows. It can gather shadows from people or things to increase its own power, but these shadows fade when they are exposed to bright light, leaving only Shadow itself behind. According to Keroberos, "Shadow can touch us, but we can't touch it."
Shadow looks like a cloaked figure in a black cloak and hood resembling the Grim Reaper.
14. 盾 The Shield
The Shield (盾) is Sakura's most-used defensive card, able to create a shell around its target that is impenetrable to almost all physical and magical attacks, including the effects of other Cards.
When guarding an object, Shield appears as a blue-white-green sphere or dome. For all other uses it is a single 'Clow Wing' shield with a red jewel on both sides. In its card form the Shield is chained by several chains for some unknown reason, like the Sword.
15. 剣 The Sword
The Sword (剣) is able to cut through almost anything, including magical barriers. The card gains its strength from the heart of the person who wields it and gives the wielder the skills of a master swordsman. However, Sword can also overwhelm and take control of the person holding it, especially if he or she is non-magical. Sword is so powerful that it is even capable of penetrating through the Shield.
Although Sword has its own form, Sakura is only able to use it by binding its power to the sealing wand, turning it into a sword. Its hilt and hand-guard resemble Clow's wing emblem. In its card form the Sword is chained by several chains for some unknown reason, like the Shield. Unusually for a sword, Sword finishes in a diamond shaped tip, rather than a conventional tapered or chiseled tip.
16. 雷 The Thunder
The Thunder (雷) is able to summon a bolt of lightning, similar to Syaoran's often-used "Raitei Shourai" spell, and is one of Sakura's early offensive cards.
In its visible form, Thunder resembles a large wolf and is made out of crackling blue-white energy. Its appearance is similar to Japanese mythology, resembling a raiju or thunder creature.
17. 水 The Watery
The Watery (水) is one of the four elemental cards. It has a very temperamental personality and is able to control water and create whirlpools and tidal waves. Watery appears to be female, although her looks are somewhat boyish.
Watery is able to absorb power from other water-based cards like Rain and is one of the two elemental cards directly linked to Yue (the other being The Windy).
Watery resembles a blue mermaid with webbed fingers and large ears that appear to be a cross between webbed flippers and pointed elf's ears. It has no legs but instead rides on a column of water that resembles a tail. Watery can also dissolve itself into any body of water, becoming indistinguishable from its surroundings.
18. 風 The Windy
The Windy (風) is one of the four elemental cards. It has a gentle personality and is able to control winds and create powerful whirlwinds. It is one of Sakura's most useful cards, as it helps her capture other Clow Cards by binding them in its winds.
Windy is mostly yellow-colored and looks like a woman with wings (like a Butterfly) on her shoulders and coming out of her forehead.
19. 樹 The Wood
The Wood (樹) is a gentle spirit that is able to create trees, branches, and vines. Sakura often uses Wood to form cages with which to trap other Clow Cards.
Although Wood can form herself into trees and branches, her natural form appears to be a small mossy green and yellow wood nymph about 8 inches high. She has long green leaf-like hair with vines and wears tiara made of leaves.
List/info taken from Wikipedia.
Also to note: I'm taking Sakura from the end of the (whoops) right before the time skip into middle school, of the manga, and may or may not borrow elements from the anime. But mostly manga. I might end up referencing something from the anime without realizing, though, as I'm more familiar with that s-so hit me if I do. '''orz