Hold your pen so that the nib is at around a 30-degree angle to the writing line. The angle at which you hold the pen determines where the thicker and thinner portions of the writing will be. As a result, most calligraphy alphabets have a specified pen angle. The angle is assuming that the horizontal line that you are writing on is at zero degrees. See Resources for a diagram.
Practice drawing some basic shapes. Draw simple marks, like a series of vertical lines, curved lines and diagonal lines. Aim to produce unified and identical marks, keeping your pen held at the 30-degree angle. Having a sturdy hand helps you in making clear and defined marks with your pen. Practice other shapes, such as circles or zig-zag lines. See Resources for a list of exercises.
Draw the first part of your chosen letter. Script alphabet letters are broken down into steps to help you master the art of calligraphy. For example, when drawing the letter "a," start with the strong line on the right of the letter with the curves flicking out at either end. The letter "e" is drawn by starting with the half-moon "c" shaped curve that makes up the bottom left portion of the letter. Build up your letter through small shapes like those in the practice exercises, and remember to keep uniformity in your pen angle.
Add in the next part of your chosen letter. The letter "m" is a good example of how letters are built up step-by-step. The vertical line furthest to the left is drawn in first, and then the next two vertical lines are drawn in, along with the arches at the top, in two downward curving strokes. Make an "o" by doing the lower left half of the circle first, and then fill in the other half in a separate stroke. You can move on from the basic "o" shape to form other letters such as a "Q" or "g." See Resources for full diagrams detailing the construction of the script alphabet.