Hi, I'm Mike Patrick, and this is how to do the instant knot trick. You simply take the rope and you toss. Sorry, you're supposed to snap your fingers. And then you get the knot to appear inside of the rope. The way this works is you tie a knot in advance at one end of the rope. You place this into your hand like this, and when you take the rope out, the knot is concealed.
You say, "I'm going to try to tie a knot with my hand like this." You simply grab it, you hold it between the index and thumb, and you toss it down once, twice, and on the third time when you do it, you maintain this grip and you let go with the rest of your hand, and it looks like this knot just appeared and like you tied it. So in real time, it goes one, two, and then if you snap that adds the visual element and it makes the knot appear. And they can untie it and see that it was a real knot. And that's how you do the appearing knot trick.