Have you ever realised that you are in the shower but barely present? I have. I realised that I would soap myself, shampoo and condition my hair, and sometimes even brush teeth while the water is still running. Completely absent from the present moment.
Here is a quick guide if you tend to shower unconsciously too.
Rinse off soap.
Use the on & off method above and continue with your shower ritual. Shampoo, condition, brush, floss, oil pull, etc. Sounds very basic and simple. Even obvious. Try it. It is very calming and you would realise that you tend to linger in the shower longer than necessary because of your mind.