Guys, he ( Assumption from the fact that his nick is ...kta)  is asking what are the documents he need to present @ the embassy. I would assume that he doesn't have valid F-1 visa stamped on his passport. Under this condition he is advised not to go Nepal if he intends to return USA.

Nepal1kta, Please, mention what the expiration of your F-1 visa on your Passport is. If it is not expired you are good to go. Otherwise, you won't be able to obtain a F-1 visa on return from Nepal when you show your OPT card and job offer @ the embassy. You can talk with your international student office personnel too.