How can I design my own social contract with at least three societal rules with explanations as to why I think people should follow them?

A social contract is essentially the beginnings of a governmental structure, like the code of Hammurabi and other ancient contracts. In my social contract, these are the three items I would legislate.
First: the right to life. This one is obvious, as people should definitely not be killing one another, but It would have other implications, such as the ability to appeal against the death malty for crimes and a right to services that protect and extend your life.
Second: right to trial, even in the absence of other laws, the right to a trial ensures that crimes and disagreements are discussed in an assembly and therefore everyone’s voice is properly heard.
Third: standing civil service organization. This is not an individual right, it is what the people give up. In order to protect everyone, enforce laws, and serve the community, a civil service group, incorporating police and service officer will be maintained.