Showing movement in your drawings is an important component to making them more realistic. Showing movement can be done in several different ways: movement lines, muscle tension, clothing draping and hair movement. These concepts give characters the perception of movement and allow for plenty of creative fine tuning.
Draw movement lines are probably the simplest way to show movement in drawing. Used mostly in comics, these are simple lines coming from a person or object. The example picture shows this concept. Lines and waves are following in the ship's wake to show that it is moving forward.
Draw muscle tension in animals and humans. This is a great way to show that the character is in motion. To show a character with muscle tension, make the muscles that are being used a little larger than normal.
Create clothing draping may be the most fun way of showing motion. A person in motion will have his cape flowing behind him, a dress billowing away from her legs, or sleeves falling away from the wrists. A general rule of thumb is that the clothing will move away from the moving body part. Hair works under this rule, as well.
Create hair movement. . As the body goes into movement, the hair will move away from the body. If the person moves forward, the hair moves back from the face. Even short hair can show movement, such as wind moving across a still animal for example.
Clothing draping should always be your go-to technique for showing movement in humans.
Movement lines are best in comics and don't work well in serious compositions.