How do you turn shampoo into cologne?

To turn shampoo into cologne, you can dilute the shampoo with a carrier alcohol, such as vodka, to reduce its viscosity and enhance its fragrance. Mix one part shampoo with three parts alcohol in a spray bottle, shaking gently to combine. Optionally, you can add essential oils to customize the scent further. Allow the mixture to sit for a few days to let the aromas meld before using it as a cologne.