Here’s a great little pocket trick that’s perfect for the beginner in magic. Self-working; very easy to do!
Two plastic pillars are shown with a piece of string running through them. One end of the string is pulled and the string passes through both pillars until it is stopped by the knot at the opposite end. This is repeated with the opposite end and again the string passes through both pillars until stopped by the knot at that end of the string.
Now a blade is placed between the two pillars and is used to cut the string running between them. The pillars are separated to show that the string has been cut. Magically, when the pillars are placed back together, the string is restored as the magician pulls it back and forth through the pillars!
There is no preparation required. It is always ready to go. A sharp blade is not required to cut the string. You can just mime the action if you wish or use a flat piece of plastic like a credit card, etc.