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Calligraphy letters are drawn using thick and thin strokes to create shapes. They are not written like traditional letters. This ‘thick-and-thin’ effect creates a flowing, consistent pattern.Here are basic rules to follow:  Keep the pen-angle constant Don't push too hard on the nib Draw parallel lines and even curves. A ‘calligraphy nib’ refers to a pen tip that is broad and flat instead of a more commonly rounded point pen such as a fountain pen. This wide, flat structure allows the nib to create a unique ‘thick-and-thin’ effect which is what makes calligraphic letters look fancy. Nibs come in different widths, so having several will allow you to experiment. It is important that you hold the pen so that the tip of the nib points away from you and to the left, at around 30° to 60°. The angle will vary depending on the specific script that you want to create, or naturally with the way you hold the pen. As you write, the nib should never turn to form lines and curves. The trick to creating beautiful, uniform calligraphy is to keep the point in the same direction. This is why you will have to pick your hand up to create several strokes that form each letter. Each stroke follows a pattern and shares similarities with other letters. Form each stroke by gently leading the nib across the paper. Your strokes will move backwards, forwards, and sideways from the direction the nib is pointing. Your hand, wrist, forearm, and elbow should not be touching the table. By fully supporting your hand and arm, it will help you keep a light pressure on the pen to help your strokes flow.  You may damage the nib if you press too hard. If you lean on the pen, your letters may not flow, and your arm may get tired.  By pushing the nib incorrectly, it may dig into the paper and blot. Always follow the strokes of calligraphy. Regardless of the specific type of calligraphy you draw, this same rule will follow. For example, italic calligraphy is created with lines that slope away upwards to the right, while Roman letters are drawn with perfectly vertical, straight-up-and-down lines. Each skill focuses on the practice of accurate angles. Drawing lines that have the same angle as each other is just as important as keeping your pen-nib at a constant angle. If you draw lines at the correct angle, they won't look right if your pen is not kept at the correct angle. Never alter your pen angle for different line strokes. As you form each letter, you will constantly be picking the pen up from the paper to start new lines. To keep your pen angle accurate, do not move the pen from your fingers before finishing a letter, and do not twist the pen around between your fingers.

Summary:
Learn the foundation of calligraphy. Get a variety of nibs. Hold your pen at a constant angle. Maintain proper form. Do not press hard on the pen. Draw vertical, horizontal and diagonal lines parallel with one another. Beware of the different angles.