Create a joke or humorous story that can be told in three panels. Write down the dialogue you plan to include in each of the panels. For example: "Panel 1: Patient to psychiatrist: 'Doctor, sometimes I feel like a wigwam and sometimes a teepee.' Panel 2: Psychiatrist considers this. Panel 3: Psychiatrist: 'You know what your problem is? You're two tents!' "
Decide how you want your characters to look. If your text is very funny, you may not want to create funny-looking characters. Sometimes jokes are more humorous when the characters look and act fairly normal but are placed in funny situations. Write down a physical description for each character. For example: "Patient: middle-aged woman with messy hair and exasperated expression. Psychiatrist: young man with mustache and wire-rimmed spectacles."
Draw, with the assistance of your drafting triangle, a horizontal rectangle on a sheet of paper. Make the rectangle much larger than it will appear in your newsletter, so that you won't have to draw your illustrations and text extremely small. (You'll reduce the comic strip before inserting it in your newsletter.) With your triangle, draw two vertical lines within the rectangle, so that you have three comic-strip panels of relatively equal size. Go over your penciled rectangle and boxes with a fine-point black marker. Make several photocopies of your comic-strip template so that you won't have to re-create it each time you draw a new strip.
Pencil a rough sketch, with your word bubbles and text, on one of your photocopied templates. Use the sketch as a guide for your actual comic.
Draw your characters in pencil in the first panel, along with word bubbles large enough to accommodate your dialogue. Repeat this process for the second and third panels. Write your dialogue in pencil in each of the word bubbles. The text should be in block capital letters so that it's easy to read. If your bubbles are too crowded with text, pare down or eliminate some of your dialogue.
Go over your drawings and text in marker. If your newsletter is in color, you can use various colored markers; if it's in black and white, stick with black, gray and brown. Make sure your text, however, is in black ink because you'll want it to be reproducible and legible. Be careful not to smear the ink while coloring your comic, and use correction fluid if you make a mistake. When you're finished, let the ink dry for a few minutes, then use an eraser to remove any extraneous pencil lines.
Scan your comic strip and upload it into your design program, and then reduce the strip to a size that's appropriate for your newsletter.