This is my sketch.

This is my first wash with yellow ochre and cerulean blue for the sky, a little cobalt for the water.

Adding background trees and distant view with mix of cobalt and yellow ochre.

Tree and shadow are dropped in with a big brush mix of burnt umber, alizarin and ultramarine.

Drop in the boats with ultramarine, cobalt and a bit of alizarin.

I add the details on the marina, boats and people and it's finished.