Because of the special pen, calligraphy takes a bit of getting used to. A calligraphy pen creates narrow lines if it's moved in certain directions, wide lines when moved in others -- all dependent upon the amount of pressure you put on the pen's nib. Mastering this technique so that it becomes second nature is nearly as tricky as creating the fancy letter shapes. Print the entire alphabet in several calligraphy fonts that you enjoy; then practice recreating the letters by hand.
Things You'll Need
Alphabet printout in your favorite calligraphy font
Calligraphy marker or pen
Lined non-bleeding paper
Place a piece of paper in front of you and hold the calligraphy pen in your hand, rotating the pen so the tip creates a wide line when you pull the pen in a straight line toward you on paper, as if you're creating a capital "H."
Draw a horizontal line without rotating the pen's alignment; note how the line is thin. Print the word "the" and write it in cursive in your usual handwriting, again keeping the marker aligned so the widest line appears during a vertical stroke.
Doodle a bit, making horizontal, diagonal and vertical straight lines as well as curves to get a feel as to how the pen behaves in your hands, paying attention to the angle of the tip as you write and draw.
Examine the letter "A" in your chosen calligraphy alphabet, noting the places where the lines are thickest and thinnest while considering the appropriate marker-tip angle for each type of line.
Re-create the letter "A" with the marker, turning the body of the marker as needed to create lines similar to those on your example alphabet sheet. If one part of the letter doesn't turn out as expected, try again, turning the pen a different way when you reach the problem area to achieve a different outcome. You may need to rotate the pen tip several different times in one letter to create the line thickness variations.
Copy a lowercase "a" or the letter "B" if practicing a capital-only alphabet. Continue with each letter until you can re-create each one fairly well on the first or second try.
Write a few words in the chosen calligraphy font once comfortable with the writing style. Try again without looking at the reference printout to see how close your result is to the original letters.
If mastering the feel of the pen and the shapes of letters at the same time is a bit too much to handle, practice doodling for a while with the calligraphy pen, rotating it several different ways and noticing the tip alignment to get a feel for how to create the various line thicknesses found in calligraphic fonts. Even a chisel-tipped marker may be used to write in this style. Write in your usual style, rather than a calligraphy font, until the pen motions make sense.
Try several different types of papers to get a feel of what you prefer. Some types of papers absorb ink too much, resulting in blotchy letters. Ask a craft- or art-store representative to recommend an inexpensive pad of appropriate paper to use with your chosen calligraphy marker to hone your skills.
If your letters don't turn out quite the shape or size you intended, print out a calligraphy alphabet on graph paper with each letter at least 1 inch high. Note how many squares wide and high each letter is; then recreate them on a clean sheet of graph paper.
Once you are completely comfortable with a calligraphy marker, try different tools, such as a refillable pen with an old-fashioned nib.
Practice your technique many times on scrap paper before attempting it on expensive paper or card stock. When you have a good feel for the pen and the writing style, progress to the actual project you have in mind.