I would like to apply a visa for travel to Morocco from Tehran.
How can I make an application?
At risk of sounding a bit obvious, Google's first two entries should be the Moroccan consulate in your country, and www.moroccanconsulate.com/Visa_new_form.pdf
You should definitely read the associated pages on the Moroccan consulate as regards requirements and restrictions - this will be important. We also have a range of questions here (look in the Related sidebar to the right) especially this one on supporting evidence.