Magic is just like anything else. It requires practice, practice, and more practice. There's just no way around it. Don't beat yourself up if you don't start getting things right away. Some of this stuff takes time and some of it is just about building up muscle memory. Some ways you can maximize your practice time though included a few little tips that we're going to go over.
One, use a mirror. Better yet, tape yourself. You've got to remember that when you're practicing a slight or when you're practicing any maneuver really, with cards or coins, the angle you have from top down, isn't necessarily the same angle that your spectator is going to have standing across from you. So it's really important to manage those sight lines and make sure that everything is clean by practicing in a mirror or by watching yourself on tape over and over again until it's flawless.
Another great way to practice is to practice the real version of whatever move you're trying to fake. If you're trying to make it look like a coin is going from one hand to the other but it's really not, practice moving a coin from one hand to the other. It's the only way you're going to know what it actually feels like.
Also when you're practicing, try to think about what it would be like if you actually had those powers. What would it look like if you could actually make a card float into the air? What would it really look like if you could really snap your fingers and bring a card straight to the top?
If you think about those kinds of things you'll find that the effect will start coming closer and closer to simulating that. You don't want it to be a trick; you want it to be amazing.