Don't be immoral in your community. Some people have to be immoral because their nature is weak, so they hide it, and keep it within closed doors to be sure nobody knows about it. Most of these moral concepts in prisoners are from their respective societies, so it is more than fair to say you can judge each society by the qualities of its prisoners in each and every state, and country. To be truthful, every prisoner's perception of each other is exactly the same thing, so where does that leave a prisoner's first impression of his new institutional environment, particularly if it's death row. We think and feel like the average person, until we find out otherwise.
Prison is no different, the stakes are simply higher.
Supposedly, everyone is a tough guy, or a killer. Many are not guilty, but we won't go into the guilt or innocence subject, but keep those thoughts in your mind. Being friendly and nice are not the standards of this society, so you either live within those standards, or you allow yourself to be preyed upon. It's really not a simple question, especially if you've never been to prison. Either become a predator, or remain the prey, but the bottom line is everyone are predators and everyone are preyed upon, so in prison you experience both at the same time.