The first stage of this watercolor was applying very wet light washes. I do it with a big brush that holds a lot of water. I keep the pigment very light...like the value of light tea. you can also apply a little more color in the wet areas while it is still wet to get interesting wet on wet effects. But what is also very important is to save those areas of white. That will add sparkle to the watercolor later.
It is hard to truly regain white areas once it is painted.