When I am at the shore and look at the waves, I think of the "coming and going, coming and going, coming and going....".
Sometimes, when I have difficulties with my concentration (for example when I had a difficult day) and I need to calm down, I think of the waves and it is eaier to me to focus my attention to my breath.
Waves are coming - I breathe in, waves are going - I breathe out.
The waves get united with my breathing (in my mind and my feelings) and I let go.....
Unfortunately I do not live next to a shore.
Many greetings from