This is a fascinating subject, and one which goes right to the heart of strong magical performance.
First up, I think we need to remember that a close-up magic trick is effectively a small piece of intimate theatre. Even if it's semi-improvised, it's at its most effective when there's a good story structure with a beginning and middle and an end. Or, as the classic quote goes "a beginning, a muddle and an end". In other words, the structure should be like this:
- Beginning - the premise is clearly established (e.g., the spectator has a freely-selected card in their mind and a magician who was nowhere near when the selection took place is going to attempt to glean its identity).
- Middle - there is some sort of conflict which stands in the way of success (e.g., the second magician is finding it difficult to get the information from the spectator's mind).
- End - resolution (e.g., the second magician, despite his difficulties, manages to identify the card).
Sometimes, as magicians, we forget about the middle part, so we just establish the premise (e.g., the card is in the middle of the deck), and then skip right to the resolution (e.g., its jumped to the top). That would be like a detective film where a dead body is discovered, the murderer gives themselves up without a fight and the credits roll. It's not a particularly satisfying story. If it's that easy, then who cares?
As magicians, our audiences don't know whether what we're doing is easy or difficult, so we get to choose how they see us through our performances. If it's something as simple a revealing a card, make it look difficult. Make it seem like you're having to exert every ounce of your skill and concentration to even just get whether it's red or black, and then push yourself even further to get the suit. Then, when you say something like, "OK, so there are thirteen values, so this is the really difficult bit", then tension is ramped up for the climax. If it was that hard to get a 50/50 choice accurately, imagine how much it's going to take to get a 1 in 13 right.
I mentioned tension there. And I thought I'd mention it again because once you've started thinking of magic performances as theatre, then building tension is going to be your favourite hobby. A lot of it is about timing and pacing, and making sure your audience is genuinely with you and isn't just politely waiting for the end. It's something that will develop with time and thousands of performances, but you can definitely give yourself a head-start by breaking the stories of your tricks down into the three-part structure I've suggested.
