In the video below, I’ll show you four different methods you can use to force almost any number for a magic trick or card trick. (One trick I use this for is the Mnemonica Any Card At Any Number (ACAAN) found here.
The first method involves using an analog watch with a turn dial. (It won’t work with an electronic watch)
This is an old method that is used by some famous mentalists such as Richard Osterlind. (See Richard Osterlind’s tricks & teachings here)
Another method involves a calculator. You can even use the one on your smart phone. It’s commonly referred to as the TOXIC force.
There are two other forces to get to some specific numbers, such as 7, 9, 14, or 21. One of these number forces requires the use of dice.