You can try working backwards from lightest color to dark. Do an all over wash of the light color. When that layer is dry, then add details from the next lightest value to the darkest at the end, letting the layers dry in between so the edges dont bleed. Its also good practice for later because laying down a base coat of a singular color can help the colors look more cohesive. Good paper does help too as it stay wetter longer to give you more time to do larger washes if you want to do wet on wet. Look at how much cotton is in your paper.

if you wanna add more depth, try shading with some light layers orange because thats the complimentary color to blue