Step 12 To stop the watercolour layers appearing too static, I added a couple of position keyframes (press P when the layer is selected) to give a nice, slowish, roughly diagonal motion over the ‘lower dog’ layer.
Step 13 I did the same for the second watercolour layer, but made it move in roughly the opposite direction. It and the first layer should overlap and move in a more organic way like this.
Step 14 Next, I added a solid – I’ve made it deep indigo but the colour doesn’t matter – between the two watercolour layers and the ‘ripple’ layer. I set the blending mode to Multiply and played with the opacity until I got a nice balance between saturation and transparency.