Spam
Clearly lay out what constitutes spam.
Personal attacks
Explicitly menton that personal attacks won't be tolerated.
Doxing
Protect the personal information of your members.
Illegal activities
Ban illegal activities such as sharing copyrighted material.
NSFW content
Define what would be considered NSFW and what would happen when someone posts such content.
Discrimination
Write down how the community would mitigate discriminations such as racism, sexism.
Trolling
Guideline for what happens when someone invokes quarrel and posts inflammatory content.
Misinformation
Stop members from posting fake news.
Multiple accounts
Would you allow the same member to create multiple accounts?
Cross-posting
Allowing duplicate content if it is relevant in two different topics.
Grammar
Will there be an automated message asking the member to post again with correct grammar?
Moderation disputes
If someone wants to dispute the moderation decision, list down the options (e.g., contact form, private message).
Becoming moderator
If a member wants to become a moderator, how can they become one? What would be the general step?
Upvoting
How should the members use the like or upvote option?
Flagging
How the members can flag low-quality content and members who are breaking rules.