Keep in mind that these policies are ultimately guidelines. If it's found that a policy restricts something that the reason the policy was created didn't intend to restrict, then the policy should be changed.
This is the Narutopedia's Manual of Style, please do not do any reorganisation and cleanup of wikitext on the wiki unless you are fixing things to follow this style guideline.
(main) - The beginning section with general intro. This is the one without a section name.
Background - Historical and background information on the character.
Personality - Information on the character's personality.
Appearance - Physical description of the character.
Abilities - Information on the characters special abilities and techniques.
Kekkei Genkai - Specific Kekkei Genkai abilities.
Other info - Things like Naruto's history with the Demon fox should be placed in this area. Or perhaps made as a subsection of an appropriate section.
Part in the Story - Section container, the characters actions within the story would be here.
Some other arc
Trivia - Trivia items. Organised in list format using * at the start of the line (Stylistically a space after that * would be nice.) Things not worthy of being in trivia include: "That X is the first Y to do Z." or "That X is the only Y to do Z." etc.
Quotes - Character quotes. The character shouting out a Jutsu name shouldn't be considered a jutsu though. Organised in the same way as Trivia. If there are multiple language forms to a character quote, it should link to an article like Dattebayo and Believe it!.
References - Just the ==References== section with a <references/> tag below it. To collect the <ref></ref> tag info in the page. Individual bits of info should be tagged with specific citation other than just the general sources section.
We use "Part II", not "Shippūden" for headers, otherwise we would be using "Naruto" for Part I which would be confusing and unnecessary.
The Part I and/or Part II headers should be dropped for any character who only appears in one part or do not have a large appearance in the other (Like the Akatsuki which only make minor appearance in Part I)
A lot of articles on the wiki haven't been style fixed, use of the ==Part in the Story== header is the proper form, please do not remove these just because you see them missing in other pages.
When used in articles arc headers should be in the form "Some Named arc" not "Some Named Arc."
"filler" should not be inserted into arc names.
Articles should be written in British English, not US English.
Articles should be written in past-tense, not present or future tense.
Articles should be written in an in-universe style, this includes calling characters by what they were called at this point in the story, and not refer to the reader or viewer when talking about events.
Articles should be independent of any point in the series, it should not be required that pages be updated every time a new event happens in the timeline simply because articles were written from the perspective of someone reading on the latest chapter.
If you use the word "current" anywhere in a phrase to refer to something, you likely wrote it the wrong way.
Headers should be in the form ==Header==, not the form == Header ==. This only applies to articles, image pages use == Summary == automatically and talkpages are free form and no changes should ever be made to header style.
Things like [[chidori|chidori]] and [[Chidori|chidori]] are pointless, only [[chidori]] should be used.
Don't bypass redirects using things like [[Sasuke Uchiha|Sasuke]] make use of the redirect properly with [[Sasuke]].
Common improper style changes
Do not change "Pain" to "Pein", "Pain" is the correct name.
Do not change "Nine-Tailed Demon Fox" or "Nine Tails" to "Kyūbi."
Do not change "Hyuga," "Shippuden," or anything to a 'uu' such as "Hyuuga," or "Shippuuden."
Do not go adding last names to links unless you have a valid reason to do so (full character name hasn't been used earlier in the article). Full names should not be abused to bypass redirects.
Do not change page numbers in ref tags to have a leading zero. Going around the wiki and changing 3 to 03 despite most pages sticking to 3 doesn't improve the wiki at all and just adds pointless edits, just stick with 3.
For the Sage Mode and its techniques, we use "Sage" instead of "Hermit."