Only include a few panels horizontally. You should never use more than four in a row. Stagger your grid gutters. The gutter is the blank space between each panel. Staggering the gutters helps to differentiate each panel.
A six or nine panel grid is good for showing continuous action like someone walking or to simulate the pan of a camera. Skewed grids can be used together to show a lot of action happening at once on a page. Instead of drawing squares or rectangles, draw parallelograms to create motion.
Plan your focal points out so that the reader’s eyes follow each one down the page in more or less a zigzag formation. For horizontal panels, place your focal point in the left, right, or center portion. For vertical panels, place your focal point in the top, bottom, or middle third. With a square panel, you can put your focal point anywhere, so the key here is to place it somewhere that guide your reader’s eyes to the next panel.
To practice, you can draw a line of action with an arrow pointing the direction you want your character moving. Draw this line in pencil and the use it as guideline when drawing the rest of your character. The line of action should be fluid so that we can see the intentions of your character’s movements. Don’t be afraid to exaggerate. If your character is pointing, the line of action starts at the feet and moves up through the body, extending through the arm.
Each pose has a rhythm to it, and your center line is what depicts that rhythm. Say your character is running, a center line that is more or less vertical isn’t as action filled as a center line that curves. Think about how the body should be leaning forward to depict more motion.
Incorporate expressions to indicate an action or event is about to happen. Even if you’re drawing a character’s face in a panel before the one where the action will happen, draw that character so that there is an acknowledgement of the pending action. For example, if your character is watching the beginning of an explosion, draw the eyes wider, the mouth open. Use your center line, or line of action to depict the character reeling back as if preparing for the explosion.
Lettering advances the story and should follow the same zigzag method to facilitate an easy to follow flow for the reader.
Think about the onomatopoeia of your sound effects. If you’re writing “BLAM” to show a gunshot, consider what those letters should look like. Are the big, bold and colored in to create a loud, ringing sound? Or are they hollow block letters that sound more like a quick cracking noise. Place your sound effects somewhere that draw the eye to the next panel.
If a character is running at you, draw lines like the iris of an eye around the character to make it look like that character is moving forward. If a character is moving left or right, draw speed lines trailing your character. Another way to draw action is to draw spit or debris flying. If someone is getting punched, draw trails of spit flying away.