This quickie will show you How to Draw a Cloud using Inkscape.
Start with an Ellipse.
Make a lot more of these Ellipses all varying in sizes.
Place them so they are all touching each other in a random Formation.
Continue to make more of these Formations in varying shapes and sizes.
For each Formation select it and Union all the ellipses together. ('CTRL' + '+')
Change the color of each Formation to light and dark shades of your chosen color.
Let's start making our Cloud using these Formations.
It's probably a good idea to start with your biggest.
Place each Formation on top of one another however you like.
Raise and Lower your formations as needed.
Then set the Blur of the entire Cloud to whatever you find suitable.
Go back and change the individual Colors and/or Blur values until it's to your liking.
Try out some colors other than the Gray I used.
Such as Blue, Red, and Yellow