1-Get up-to-the-minute info from other travellers on the iran branch of the Thorn Tree:
2-Get visa through Agency in iran and don't waist your time in iranian embassies
3-Ta'arof(very confusing iranian cultural rule for politeness) ,if you ask a taxi "How much?" and he answer "Ghabeli Nadare" it means "don't mention it" but this is Ta'arof and you must say thank you and after 2 or 3 times he will accept your money.
4-get some information about today politic of iran to discuss with young iranian who are politician generation.
5-there is a lot of zero in iranian money,but confusing part is writing in Rials and Talking in Tooman(One zero less than Rials)
6-if you have travel books like Lonely planet or Etc , prices are higher than what you have on them because of inflation 13% to 25%
7-No Credit cart And travel Cheque Accepted in iran
8-Alcoholic Drinking NO
9-If you are a Carpet collector, be sure iran is your Paradise
10-Outside WCs mostly doesn't have toilet papers
11-siesta time will close most of shop and some monument as well ( 13:00 to 16:00)
12-driving in iran is horrible so do crosswalk training if you don't want to have hospital visit.
13- bring your family photo if you want to communicate closer to Iranian
14-mineral water are in all over country founded but even though tap water is drinkable and good.
15-to fly back to home, sometimes you need 2 hours to pass Tehran traffic and reach IKA Airport.
16-pickpocket are not common in Iran but wear a money belt and put your hand on your wallet or purse in all busy places in crowded city
17-don't buy/sell currency from dealers around imam square in Isfahan or Karimkhan Castle in Shiraz,in exchange shops has better rate.
18-there is a lot of holidays in Iran that some of them close museum and monument as well, check it out from reception in hotel if you have holiday in your itinerary.
19-Farsi is spoken language throw the country ,phrase book is a useful item to carry because most of population don't speak any foreign language.
20-if you are fan of classic,drama and sad movies don't hesitate to watch movies from some iranian world famous directors like:
Abbas Kiarostami ,Mohsen Makhmalbaf and his daughters, Jafar Panahi , Bahman Ghobadi , Majid Majidi and Asghar Farhadi.
if you don't have time to search their movies , don't miss movies 1- Nader and Simin,a separation "Oscar candidate" 2- Taste of cherry 3- persepolis animation
21- if you don't have time to read iran History, at Least search about:
Achaemenids Empire , Cyrus the great, Darius the great, Sassanians Era , Safavid Era , Shah Abbas