Create 2 new Layers and take a brush tool and Set all the parameters as shown in the 1st Image and choose the colour #67b0d6 for the cloud. you can set the layers opacity as per require.
You can choose another brush tool as per the effects and shedding of the cloud.
You can change the size of the brush as per the effective cloud looks required.
the final effects you will get as shown in the 2nd Image.
1) Create a new layer and make the shape as in 1st image using pen toll and fill it with colour #bee1ed. now choose the soft eraser tool a Size-400px, hardness-0 and opacity 50% and erase the lower of the shape from left corner to center horizontally once a time, you can also repeat erasing twice or thrice as per required effect.
Go to the Layer style and Drop shadow as - Blending mode-Multiply, Opacity-18%, angle-(-172) use global light, Distance-2px,spread-0, size-16px.
Set the opacity of the layer at 50%.
2) Duplicate this layer and set as shown in the 2nd Image.
Create a new layer and male a shape using pen tool, fill it with colour #bee1ed. Set the layer style and set the layer opacity as 75%. For shadings you can also use dodge and burn tool (optional).
Create another layer over that and make the shape using pen tool and set the layer opacity as 50%.
Now Create a new layer and choose the soft brush tool, size 25px and set the colour #bee1ed in foreground, then Create a new line using pen tool as shown in Image and go to the Path Panel and select work and Right click on it and choose "Stroke Path".
Create a new layer and the set the Brush Presets shown in the Image chosen grass brush tool and make a mimosae like shape with the colour #e9f8ff and put it at the place of border of the Image so that only half part can be seen as we need. and set the layer opacity as 75%.
Now to make the circular points set the soft brush at 0 hardness and keep on clicking after setting the foreground colour #e9f8ff. you have to set the size of the brush tool as per needed to create smaller or bigger shapes.
Go to the blending option and set the parameter of outer glow as shown in the Image.