assignment contracts

about to have my first deal on contract, but now i’m concerned as to how to go about assigning it. I’ve been told a few different things, which is why i am now confuses. First i was told to write up an agreement with the person taking over the contract and have that person deposit non refundable money into an account for my fee, but somebody else told me that i don’t need to do any of that and that i just get paid at closing??? I’ve already made myself a prewritten assignment agreement that is pretty general that i planed on using for all of my assingments, but now i’m confused as to whether or not i need it. Will someone please tell me if i’m supposed to use one or not, and if i am can you email me so i can send you a copy of the contract i wrote up to get your input on it?! thanks. OH! Or, even better! If anybody uses an aggrement of their own for the assignment could you email me a copy? That would be great also. Either way is fine. Thanks.