This video was our inspiration to figure out the mathematics that makes some card tricks work.
This is just a sampling of the card tricks explained on YouTube. If you look at the accounts that posted the videos above, you will find many more. What I would like you to do is...
Watch some videos. Find a trick that you like and that you think you can do.
Try it out, use the video to help. Run through it a few times.
If you don't like it as much as you expected, go back to hunting.
If you do like it, practice it some more. Get good at it - smooth, comfortable, able to talk and tell a story as you perform the trick. Test it out on friends and family.
Also, make sure you understand WHY it works. There is something mathematical happening that makes the trick work.
Once you have your trick perfected, you will make a video.
Demonstrate the trick in the video, either using the camera as your audience or getting a person to play the part of the audience.
Then, perform the trick again but explain what is happening. Talk about the process and the mathematics that the audience does not notice.
One technique used in some of the videos above is to change the camera perspective to clue in the viewers of this change. When he is performing the trick, the camera is across the table. When he is explaining the trick, the camera is over his shoulder. You can copy that technique if you choose.