What gesture to make when hitchhiking in Iran?

As an Iranian I like to add that cultures never stay the same and always evolve like a living creature, these days the thumbs up gesture does not really indicate anything offensive anymore.

Being kinda westernized it is now the like-gesture (you all know the source), people now often use it to show approval of what the other one said or did. Though in some outlying regions it might still mean rude which I consider totally rare.

Yet we don't use the thumbs up gesture for hitchhiking, we just hold a hand forward like you want to shake hands and optionally shaking it a little up and down for getting better attention.

And you should know, it's just not illegal and everyone can actually give rides to people and take money for it which makes free hitchhiking rare in Iran. Instead it's very popular and many people will stop to get you somewhere and take some money in return. So when someone pulls over, he is expecting you to tell your destination then they will suggest a price (often low) and if you accept it you can jump in.

Finally to add something about foreigners in general, Actually Iranians are very interested in foreigners (you might often notice them gathering around you or eyeing you up LOL, just don't panic), so as a foreigner you might get free rides more (except taxis who might try to get double from you).

the thumbs up gesture is extremely offensive in Iran

Yes it used to be rude, maybe in the past years (to our fathers and grandads), but I've never seen anybody use it in Iran to show anger or disrespect, unless humorously. The important point though, is that nobody in Iran knows about hitchhiking gesture! Therefor if a driver sees you raising your hand with that gesture, the first thing that comes to their mind before thinking that you are being rude is "Why has he raised his hand like that? What's he doing?".

So what to do?
Consider the following facts:

1. Iranians are known to be friendly to foreigners, especially if they are blonde or have blue eyes! Why? I don't know. It's probably because for unknown historical / psychological / mental / environmental / racial reasons, we think that foreigners are the superior race! (But not all of them! This is mostly true about Americans, Europeans and Australians). (Ironically, Iranians, again for unknown reasons, tend to believe that they are the smartest people in the world!) Very complicated huh?
2. They also think of forefingers as being wealthy.
3. Taxis are very cheap in Iran compared to other countries.

So if you want to hitchhike, just wave your hand in front of a car to stop them, and ask them for a free ride (e.g. tell them that you don't have money - and emphasize! Make sure they understood that you are not going to pay them!). Although in the first place they wish you gave them a few dollars for the ride, they will most probably accept to give you a free ride, because they are friendly and love you! And don't be surprised if you got invited over to their house for dinner as well!

(And don't forget that taxis are cheap. Even paying 5 dollars to the driver would make them happy and is more than enough for inner city trips)

Happy hitchhiking!