Calligraphy is taken quite seriously in Arabic culture. In the past, apprenticeships for a calligrapher could start during childhood; in modern times, proper study can take five years. However, imitating Arabic calligraphy for the purposes of fun or decoration can be done with fairly simply. Arabic calligraphy needs slightly different tools than other types of calligraphy and some modifications will be necessary.
Tape two sharpened pencils together. The right pencil point should be slightly in front of the left. This makes an ideal tool for practice; an angled carpenter's pencil can work well, too. Hold the pen in your hand at about a 45 degree angle. On plain paper, practice strokes using the pencils. Try many types of lines -- horizontal, vertical, angled and loops. Find a chart showing the Arabic alphabet and practice the letters. Look at pictures of calligraphy and try to imitate what you see. Arabic writing moves from right to left.
Acquire a calligraphy pen suitable for Arabic calligraphy. This can be somewhat difficult, as pens in calligraphy sets typically have flat nibs, while Arabic calligraphy requires an angled pen. Some ordinary pens are also angled this way, such as flat felt pens or permanent markers. You can also modify a pen. Bamboo calligraphy pens are particularly easy to modify; cut the bamboo pen tip with a craft knife at a 35 to 40 degree angle, with the sharp angle on the right side.
Find an image of a design that you would like to imitate, or design your own. Designing will be difficult if you don't know the language, but Arabic calligraphy encourages creativity.
Draw a light line across a sheet of glossy laser printer paper with a pencil. This line must be at the point at which you want the bottom of your calligraphy to be and will help you to keep your writing straight.
Use the pencil to lightly draw out the calligraphy design.
Trace over the pencil design with your calligraphy pen. Wait for the ink to dry completely, then erase the pencil.
Use online resources to help you learn to write specific words in Arabic script. Decorative marks are often used in Arabic calligraphy. Left-handed calligraphers may need to modify these instructions or use a different pen.