How to put on a profile picture on facebook using the iphone facebook app?

Well i recently just joined FaceBook as all my friends were telling me to get it. Anyway i have the app on my iphone4s and i want to have a profile picture. In my camera roll i clicked on the arrow and then facebook but it then it says post. Also i tried going onnm profile and clickin on the actual profile pic bit but nooothing happens when i do. When i upload a profile picture will this mean that it will post on my wall aswell? Any help please i'm so confused!

You have to go onto safari and use their mobile site rather than the app.

If you want to change it on the app you have to add the photo and then change it

This is easy. First you have to upload a picture on the newsfeed or either your profile and once it's uploaded click on it, long press on the picture until some options come up the there should be an option saying "make profile picture" and click on that:-)

Just upload and then save it on your profile.