Calligraphy refers to the art form of fine writing that's been popular in both Europe and Asia. There are numerous styles of calligraphy, but the English style of calligraphy was influenced by both the Romans and the Goths. Therefore, looking at the letters of Rome and the letters that were used by the Goths, and how they evolved into English letters, is one sure way to get a feel for how English calligraphy is supposed to be written.
Find some examples of English calligraphy letters. Learncalligraphy.co.uk is one place that you can see not only the letters and how they look when they're finished, but the steps that you should take when drawing them.
Practice with your calligraphy pen. If you don't have a calligraphy pen, then a roller ball pen should work. Ideally it should let the ink flow, unlike a ball point pen. Get used to writing or drawing with the way the ink can puddle.
Draw the calligraphy letters. Draw the entire alphabet, and try to get a feel for how the letters are supposed to look and feel as you draw them. Keep doing each letter until you feel comfortable with it, just like you did when first learning to write.
Practice putting words together on the page. The more practice you put into your calligraphy, the better you will be at forming the perfect letters.