You can enhance your interpretation of the Tarot (and other Oracle cards), as well as frame readings around special topics, by taking special notice of central and incidental picture images in the cards. While some of the images featured in the card illustrations may seem like window dressing, just stuck in to add visual interest, Tarot designers do have to think about the backgrounds and other symbols that they incorporate, and are no doubt operating on both conscious and subconscious levels when they do so.
Although I always consider a card's weightier archetypal meanings first, and I don't normally expect to find too much in the incidental images, when items in the illustrations do have direct, often idiosyncratic, relevance to an individual, it is a dramatic reaffirmation of how the Tarot can speak to personal concerns. As an example of how objects in a card's picture space can take on pertinent meanings, I once did a "What's in the cards for today?" reading on a day I was invited to go boating, and although the cards' traditional meanings all applied to the day's overall experiences, two of the three cards drawn featured boats in the background. As another example, in my readings for other people, the appearance of the Chariot often denotes car problems. Although the chariot is a central object in this card, the Chariot wasn't intended to be about transportation, but about self-control. Nevertheless, we live in a society where having transportation is crucial to one's ability to get around in life, and therefore one's ability to be in control of one's fate.
It gets particularly interesting when the graphics in the spread make a link between images in neighboring cards. For example, if you get the Justice card, to what adjacent image are her scales held up? If you get the Hermit, to what adjacent image does he hold his lantern? In my own case, in 2007, I did a daily reading using the Hanson Roberts deck, where the reversed King of Swords was to the left of the Queen of Rods, creating a juxtaposition such that the King's downward-pointing sword was close to the Queen's tabby cat (which is in the left foreground of the picture, but curled up in a way that the cat faces forward, but its left side is on the left side of the picture). As I contemplated this spread, I had an intuition that the reading applied to my tabby cat, Kyp; not long thereafter, a tumor was discovered on his left front foot, so he had to have surgery. (Sometimes a Sword card can indicate surgery.) Had the King of Swords not been reversed, or had I used another deck, the meaning might have been the same, but the flow of images would not have been so striking, because the sword wouldn't have been directed toward the cat, and the cat would have been a different color, and in a different position.
The above example is a good reason not to jump to the conclusion that a reversed court card represents a bad or unskillful person, because by changing the direction in which a human figure is looking, gesturing, or moving, a reversal may call attention to something important in another card. There are also synchronicities at work when you are drawn to use one deck instead of another. Additionally, images within the cards might take on greater significance in cases where a card's traditional meanings don't seem to make much sense in relation to your situation or what you're asking.
Knowing that incidental images can be meaningful to personal readings encourages us to give more thought to both their popular and esoteric symbolism. Consider the Page of Cups; in the Rider-Waite-Smith [RWS] deck, the page stares at a fish that jumps out of his upheld goblet. Because the Page is generally interpreted as a person who is undergoing new inner world experiences, in that watery world of emotional and spiritual interconnectedness the fish can represent life impulses rising out of the Unconscious. Also, in amuletic usage, the fish is a symbol of luck, fertility, and abundance. In some decks, the page has a look of surprise, so it's interesting to note that the fish is also connected to Fool symbolism (as in France and Italy, where they say "April Fish" instead of "April Fool," and people pin fish onto each other as a joke). I like to see the fish in the cup as a symbol of fortuity, which means the state of having things come about by happy chance and lucky coincidences. So, the next time you draw the Page of Cups, look at any neighboring card to which the page is holding up his or her goblet, because it may reveal a situation or area of life where you feel that the Universe is playing a little joke on you, yet that is also where you may discover lucky opportunities for creative fertility.
In fact, for a little fun and edification, you could turn this into a card-search Tarot reading, perhaps to entertain your friends on April Fools' Day. We can call this "The Fortuitous Fish Finder." Choose a deck which portrays the Page of Cups holding a cup with an emerging fish up to the side, then as you shuffle and cut the cards, voice the question, "Where can I find my luck-fish?" Then, thumb through the deck until you find the Page of Cups, and look to whichever card the cup is being held up toward. (By the way, the other RWS illustration with a live fish is the King of Cups, but that one is way out there, swimming in the greater ocean of the Unconscious.)
Taking note of incidental symbols and other recurring images is one way to better familiarize yourself with your deck, and can be helpful in getting yourself aligned with the energies of a deck that has been newly acquired. You can go through your deck and observe how many times a particular symbol occurs. Some symbols that you might want to make a count of include celestial features such as the sun, moon, stars, and clouds; animals like dogs, birds, and horses; animals used as heraldic emblems in robes and furniture; articles of clothing, such as wreaths and crowns, or amuletic jewelry; architectural features like doors, windows, gates, arches, walled gardens; buildings such as houses, towers, and castles; the disposition of human figures, such as children, people approaching or leaving, falling or fallen people, etc.; ships in the distance (are they sailing out or coming in?); features of the landscape, such as mountains, waterways, and paths leading off into the distance; and much more.
You may be surprised as to how many or how few occurrences a certain symbol may have, or where it sometimes pops up. For example, in the RWS deck, there are only four occurrences of the sun: in The Sun, where the sun is of course the focal, archetypal image, and in The Fool, The Lovers, and Death, where a sun shines in the background. One might also count Temperance, where a shining crown hangs sun-like in the sky. (Although the Star engages Sun imagery, as stars are suns, the stars don't give as much light). The RWS deck does not use the image of the sun in the Minor Arcana, reserving it for the expansive, high-powered, intense quality of illumination achievable through the principles that the Major Arcana cards denote.
To elaborate the significance of the sun image: because the sun is such a high-powered symbol of life, light, and hope, it indicates a potential for revelation and life renewal. When other cards are next to a card featuring the sun, there is an expectation that some of the unconscious matters they represent will be brought to the forefront of consciousness and illuminated, and also that they have to potential to bring some genuine light-heartedness, pleasure, encouragement, and growth—even with the Death card. This suggests doing a theme reading using a card search for sun images. For example, if you are depressed or dealing with heavy hardships, you could address the cards by stating, "The sun shines for everyone; after the rain the sun, so when will the sun come out for me?" Shuffle and cut your deck (you could also hum, "Here Comes the Sun"), and then go through it until you find one of those cards with the sun in it. (In this instance, you would avoid decks that don't feature the sun in any card but The Sun.) Then, base your interpretation on which card you have drawn, and how it relates to its flanking cards.
Because Tarot readings don't always have to answer personal questions, but can be used to explore general philosophical questions, here too, we can use card search techniques. In the case of the sun image, one could pose questions like, "How can we find illumination in The Lovers' relationships?" "How can we find illumination in Death?" and so on. To demonstrate this potential, I asked this question of Death while writing this paragraph, shuffled (using the RWS deck), then located the Death card, which was flanked by the 2 of Cups (to its left) and the 10 of Cups (to its right). As a philosophical observation, this combination of cards might point out that in times of personal loss or other sorts of life transitions, individual relationships as well as larger family relationships are realigned, often bringing people together, to rely on each other more, get to know each other more, and form new family bonds. Here, too, is a striking graphic correspondence: the sun in the Death card is practically touching the rainbow in the 10 of Cups, doubly emphasizing the promise of hope and renewal.
As the card combinations that come up in Tarot readings can suggest little rituals, the above example suggests a rite for dealing with death or the fear of death. The sun in the Death card is a rising sun, because it's on the right side, the direction of the future. Therefore, a person who had drawn these cards, or anyone who wants to deal with the fear of death, could get up in the morning, face the rising sun, hold the Death card up to it, and say something like, "Though all things are transient, with change there comes illumination; so may I change my life by bringing light into the lives of others." To more fully engage this imagery, one could find a rainbow-themed cup, fill it with water or juice, toast the rising sun, and visualize oneself drinking in the powers of the color spectrum that we get from the rays of the sun.
I have found that the more I explore pictorial elements, the more I am able to experiment with those decks that provide a variety of images, including illustrations that depart from tradition. So far, however, the original Rider-Waite-Smith deck still seems to offer the greatest variety of images, because it is actually more detailed than its many spin-offs. For this reason, I have especially come to appreciate the creative vision of Arthur Edward Waite and Pamela Coleman Smith, even though they have been accused of junking up the Tarot by inserting a lot of superfluous decoration. Because a profusion of symbols in the card illustrations can stimulate innovations in divination, readings for advice, and the creation of rituals, I hope that future artists will be inspired to play with the imagery even more—showing us something that is really new, yet philosophically enhancing what we already know.