Well, I used to think so too, but then I discovered a fairly simple way to draw perfect, fluffy clouds, in just a few easy steps. In fact, I’m ONLY going to be using graphite for this demonstration. (Although you can use most of the techniques below with plenty of other media, too.)
Let’s get started!
Step 1: Lightly draw a simple outline of a cloud
The purpose of this outline is to show you where to shade sky, so the lines don’t need to be detailed. They don’t even need to be complete. As you can see in this illustration, the lines are neither dark nor continuous.
Make sure not to draw too darkly. You want a guideline that lasts only long enough to shade the sky. I’ve made this drawing a little darker than I ordinarily would so it shows up in an illustration, but the lighter you draw, the better.
Step 2: Shade the sky—not the cloud!
I used a 2B pencil and medium-light pressure (slightly less than normal handwriting pressure). I held the pencil near the end and at a nearly horizontal angle so I was shading with the side of the pencil instead of the point. I like that method because it covers the most paper the most quickly. Use the hold that works best for you and is the most comfortable.
Follow the lines you drew in step one, but don’t worry if you’re not 100% accurate. Few clouds have razor sharp edges. They are constantly in motion, growing or shrinking as they move across the sky. That motion produces softer edges, so the edges of your cloud should be soft, too.
Notice how I decreased my pencil pressure as I went down the paper, making the sky lighter at the top than the bottom. This adds even more drama to a sky.
When you’ve finished your first layer, add a second one, using strokes that go perpendicular to the strokes underneath. The goal is to cover every centimeter of the sky with at least a little bit of graphite. The only truly white area should be the cloud.
If you’re adding a slight gradient to your sky, then use the same process as before, beginning with medium-light pressure at the top and decreasing pressure as you move toward the bottom of the page.
Step 3: Blend your layers until smooth
Next, work with the graphite you’ve already put down to create a field of smooth shading and value.
For this job, a tortillon (a blending stick made of tightly rolled paper) was the most effective. I used it just like I used the pencil and worked across the sky stroking in one direction, then went back over the sky in the opposite direction. I used medium-heavy pressure and the side of the tortillon.
After that, I rubbed the drawing with folded paper towel to smooth it out a little further.
Step 4: Gently add shape to your cloud
Tortillons pick up a lot of graphite when you blend with them—enough that you can actually draw with them! I began shaping my clouds by lightly rubbing shadow shapes onto the paper using the “dirty” side of the tortillon.
Blend a little, draw a little. . . take your time, and use a reference photo to make sure your shapes look natural.
To start with, I kept to larger shapes, establishing values and contours that I could add to later. I also used a 2B pencil to draw the small, dark clouds at the bottom. They will be my “anchor darks” so I wanted them in place before getting too much done with the larger, brighter clouds.
Here’s a detail area showing the bottom part of the clouds. I alternated using my pencil and tortillon to get nice, smooth dark values in this area.
For the upper part of the clouds (which you can see below) I used lighter pressure and a 2B pencil, followed by medium to medium-heavy pressure with the tortillon to blend the graphite and draw some of the lighter shadows in the middle values.
And here’s the full drawing at this stage, to give some overall perspective:
Step 5: Increase your contrast
Once the basic shapes were in place, I continued darkening some shadows and lightening other areas with a White Pearl eraser or a kneaded eraser.
When drawing clouds in a monochromatic or gray scale, like this, it’s always a good idea to draw the sky darker than it looks in real life. You can’t make your paper whiter, so the only way to make the cloud look brighter is to make the background (the sky) darker.
I started with the sky too light to produce dramatic contrast with the clouds, so I went back over it and darkened the upper half of the sky with a 6B pencil. I used medium pressure to cross hatch graphite over the sky, then blended with the tortillon and medium-heavy pressure, repeating the process until the sky was the proper darkness.
Next I used a white pearl eraser to clean up the highlights in the brightest areas of the cloud. I made some of the highlight edges sharp and some of them soft, working back and forth until I liked how it looked.
I also rubbed a little loose graphite pigment into the sky area with a cotton swab, then blended it with the tortillon to improve contrast and make the cloud look even brighter.
Step 6: Finish up with small details
When you’re nearing the finish line, make sure to step back and review all parts of the drawing, and see if the values relate properly from one area to another.
In my case, I decided to darken the interior shadows on the left side of the cloud because they were too bright and pulled attention away from the center of interest. I also blended the sky again with a soft brush and the drawing was complete.
When drawing clouds, keep in mind that they are constantly changing as they move through the sky. Consequently, they have few sharp edges. Even the edges of a well-formed thunderhead are sometimes blurred!
Lastly, if a cloud is brightly lit, especially from behind, it sheds reflected light in a number of directions. Watch for all the different ways your cloud is casting shadows AND reflected light. There will be little highlights everywhere.