The wiki prefers historical present tense (even when certain subjects, objects, and so on, are discontinued in the Steven Universe world and only excluding for deceased subjects, past events, and subjects that no longer meaningfully exist as such) and active voice in the page's sentences.
American English spelling and punctuation/grammar are preferred save for a few cases such as the subject quote ("It's me, 'galactic criminal', Rose Quartz".).
The Oxford comma is to be used even when a series does not require clarification. It cannot be used to make a series incorrect, however.
The debate between the correct possessive style (s's vs. s') has settled for using s' for singular subjects with an s at the end to indicate the end sound is more similar to a z phonetically. e.g. Lapis' > Lapis's.
Plain English is all that is needed. Keep from using needless jargon and verbosity (like this right now) and keep it simple so the text on every page can be suited to everyone.
That is all. If you have any questions, let me know. Have fun editing the wiki.