This is an essay; it contains the advice and/or opinions of one or more Wikipedia contributors. It is not a policy or guideline, and editors are not obliged to follow it.

Please update the page as needed, or discuss it on the talk page.

Don't bite the midbies (WP:BITEM)

Some common mistakes are made (mainly in good faith) by those who arguably ought to know better, given their experience. Perhaps people just have blind spots; perhaps the relevant guidelines just aren't clear enough, or publicised well enough. For whatever reason, though, editors often don't grasp some of the following...

User ABC deleted a warning from his Talk page! Removal of warnings is allowed under WP:USER#Removal_of_comments.2C_warnings - indeed, such removal may be taken as a sign that the editor has read the warning. However, an unregistered user should take care to only remove warnings that apply to their own contributions, since another editor may be using the same IP address.
Use, abuse, and ownership of User space (User & Talk pages) The principle to remember is this: when Wikipedia refers to "your Talk page", the term "your" means "associated with you", and not "belonging to you". What you can and can't do is laid out at WP:USER and WP:TALK. Remember that (except for mainspace policies like no original research) normal wikipedia principles and guidelines apply to User space - even WP:OWN.
Where should I add my contribution...? How about... here? Lots of good faith contributions end up in the wrong place, perhaps due to a lack of understanding of WP:LEAD and WP:SUMMARY. In the first instance, an editor adds something to the first section of the article - after all, if it didn't seem important to them, they wouldn't be adding it - even though this may prevent the lead section providing a concise overview of the article, establishing context, summarizing the most important points, explaining why the subject is interesting or notable, and briefly describing its notable controversies, if there are any. In the canonical example of the second case, the editor adds their documentation to the end of the "controversy" section rather than following the {{main}} link to the "X controversy" article - which risks creating a WP:POVFORK or, at least, not providing a neutral summary of the sub-article.