You will look like you have mind reading magic secrets!
This is the best card trick to really sock your audience between the eyes with. Lots of knowledgable magicians get fooled by this because they are looking for the sneaky moves and there isn't really one. All it needs a tiny bit of confidence but if you have been watching and learning from the magic videos at Julian's Magician School you will have gained enough confidence and courage to give this a go.
You won't need to practise your magic moves too much with this but you will need to practise lying with a big smile on your face. Lying to people was one of the problems I had when I started performing magic. I'm not a natural lier and it made me feel uncomfortable. It became easier when I started making people smile and laugh and even gave them a magic secret or two to take away with them. I realised that lying to and tricking people was ok if I made their day better.
This is why I vever embarrass people when I invite them to help me with a magic trick. If I was to lie, trick and make them feel stupid then I would be the jerk. You can use your magic so much better than that.
This is really strong magic and as such don't start with this as your starting effect. It's a hard one to follow on from. Use it as an ending.
As you know from following my videos I encourage you to share a lot of these magic secrets with your audience as magic shared is much more fun. That said you should always finish strong and leave your audience with the memory that YOU are 'the magician'. So don't tip this best card trick secret. Give your audience something to think and talk about after you leave.