More powerful than a FAQ is a TOS (Terms of Service). Actual rules to post by.
For example, these (with updates) have served
Hydrogenaudio well since 2002. See especially TOS#8, which made Hydrogenaudio a pioneer in audio science websites:
TOS Hydrogenaudio Terms of Service / Notices
TOS 1. All messages express the views of the author, and are not and should not be taken as representative of the official policies of the forum or the views of its staff, unless explicitly stated as such by the authoritative members of the staff.
TOS 2. All members, at the staff's discretion, must converse in an acceptable fashion to be allowed the privilege of continued participation. The use of generative AI such as ChatGPT is strictly limited.
TOS 3. All members must acknowledge and accept that data integrity is not the liability of the Hydrogenaudio staff. Those who do not accept this should not contribute any content whatsoever to the Hydrogenaudio community.
TOS 4. The Hydrogenaudio community requires that all members provide a valid email address. This email address will only be used for user account validation and activities directly related to the features of this community, and will never be given to any third party.
TOS 5. All members that post to the Hydrogenaudio community must acknowledge and discuss only acceptable topics when starting a new thread. If posting to an already existing thread, they must continue in the vein of discussion that the thread has already manifested; if they wish to change topics, they must start a new thread.
TOS 6. All members that create new threads must use a topic title which is understandable and describes the content of the thread properly. Furthermore, all new threads must be started in the correct forum categories, and posted only once - in the appropriate category - throughout the entire forum. Double posts will be removed, and threads with inappropriate topics will be moved. A member that repeatedly violates this rule may be subject to administrative action.
TOS 7. All members must acknowledge the authority of the staff insofar as administrative actions are concerned. These issues are no longer open for discussion once the staff member has indicated that the matter is closed. Further concerns regarding an action should be communicated via a private message to the staff member, and not repeatedly discussed publicly. Furthermore, once a thread on a particular topic has been closed or removed and indicated as being unacceptable by a staff member, starting a new discussion on the exact same topic will result in administrative action being taken against the poster.
TOS 8. All members that put forth a statement concerning subjective sound quality, must - to the best of their ability - provide objective support for their claims. Acceptable means of support are double blind listening tests (ABX or ABC/HR) demonstrating that the member can discern a difference perceptually, together with a test sample to allow others to reproduce their findings. Graphs, non-blind listening tests, waveform difference comparisons, and so on, are not acceptable means of providing support.
TOS 9. All members must refrain from posting links to - or information regarding how to obtain - material that is copyrighted and being distributed without authorization or is otherwise illegal. Discussion containing information of how to obtain such material, how to bypass protection methodologies of such material, or how to otherwise violate laws pertaining to such matters will not be tolerated.
TOS 10. All members must post in English. Content in other languages are allowed as long as full English translations are provided, or otherwise at the discretion of the staff. User profile information (including sigs) in other languages is allowed.
TOS 11. All member signatures must be kept brief (3 to 4 lines at most). Signatures and avatars must also be non-obtrusive, non-offensive and work-safe.
TOS 12. All members are only allowed to have a single user account with the forums. Members who are found to violate this rule may be subject to immediate banishment or other administrative action.
TOS 13. Updates posted in the "News Submissions" forum should be of importance for the community.
TOS 14. All members must refrain from using the forum solely for advertising purposes. Spam posts of any kind may lead to an immediate ban.