How does one make silly string?

Silly String is typically made by combining a mixture of various polymers, propellants, and colorants in a pressurized canister. The propellant helps to propel the mixture out of the canister in a string-like form when the nozzle is pressed. The polymers in the mixture provide the stretchy and sticky properties that make Silly String fun to play with. The colorants are added to give Silly String its vibrant colors.