The characteristics of the ideal deck marked are very clear and easy to see in theory. It is important that the markings balance two essential qualities. These should both be true when performing under conditions.
A) The markings must be easy to read by you, the magician
b. The markings should not be easy to spot by your audience
So, the deck that is marked must look normal. This will ensure it does not draw attention to itself and doesn’t reveal the secret. But the markings must make your job as magician as simple as possible. These elements are crucial for creating a great marked deck.
1. It should use a reader. Professional magicians prefer a marked card that uses a reader rather than a codified system. A coded system will reduce your risk of being found, but it will require you to be much more attentive when performing. You will often have to do quick mental math to find the correct card. Perform magic and you want your job to be as easy as possible so that your mind can be occupied with good presentation. A reader system makes sense. Your spectators might not be able understand a system coded with obscure symbols. Although it might be true, it’s not very practical. Instead of trying to focus on the details, your presentation and your technique, you’ll be able to concentrate on what you are doing. This type of multitasking is a distraction from the actual work you are doing.
2. It should be large enough to display the markings. Large enough markings should be visible at a glance and easy to read. A lot of marked decks get praise from relative novices because they have a marking system that is nearly invisible and virtually undetectable. You may find that these marked decks will withstand close scrutiny and examination by your observers. Even though tiny markings are not visible to spectators they can make it much more difficult for you to read them as a magician. This makes it very difficult to perform. I have seen many comments from magicians who dismiss certain marked cards simply because the markings don’t fit their eyesight. Spending too much time looking at the back can lead to confusion.
3. It should adequately hide the markings. It is important that the markings are not so obvious that your spectators will be able to tell that it is a marked deck. A card back with design elements that are intricate and decorative will conceal the markings well from muggles. A good deck with marked markings will have the markings placed in the artwork of back design in such a way that they won’t be noticed by anyone except the very attentive observer who carefully examines them.
4. It should have markings at the long edges. It is best to show a deck facing down in a spread, or fan. In either case, you won’t be able to see the long edges of cards because they overlap. You need to be able to identify the card quickly by looking at its markings. If the markings do not appear in the centre of the card backs then it will be impossible to identify the card when it’s part of a spread. This is again a characteristic that is primarily determined by the necessity to be practical as well as functional.
5. It should appear as normal and natural as possible. To reduce suspicion and heat around your deck, you want to make it appear like a normal deck. Professional magicians demand that their deck look the same as the one they use to perform their other magic. Unusual decks could be misinterpreted by spectators as a “trick deck”, but custom decks are gradually becoming more acceptable. One drawback to decks with intricate custom artwork is their potential distraction from the magic you’re performing. When you do card magic, it is important to have a deck that says “normal deck”, isn’t suspicious, and doesn’t draw attention. This also allows you to give away cards from a nonmarked deck of cards to spectators without the risk of them finding anything unusual on the card backs.