Hi i would like to ask one question.

Let's say if im going to sell a stuff and COD with the buyer.

What are the things should I do ?

For example, should i prepare a paper of the details of the transaction and both the parties sign on it ?

This is the first time im selling a stuff, so any help would be appreciated.

Im juz afraid if later got any problem, then i would not have any evidence to back me up.

Thank you