Simple guide for simple illustration :
Drawing simple cartoon cloud using inkscape
Start:
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1. Use circle tool to draw two oval. Select both oval shapes and perform a union clipping.
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2. Fill the cloud shape with white.
Duplicate or copy the cloud shape, now we have two cloud shapes.
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3. Duplicate the newer cloud shape. Slightly move the top shape.
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4. Select both shape > Path > Difference to clip the selected shapes. Fill it with light blue and makes the stroke invisible.
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5. Place the clip to the first cloud shape, slightly blur it.
The finish simple cartoon cloud .