additions from someone who has posted way too much on this site please listen to me:
there are no best times to post but generally sunday and monday are a good zone for traffic
you must double check and make sure the publication date matches the day a chapter is posted or it won’t show up on the first page of updates. sometimes you have to physically edit the posting date multiple times for this to be fixed.
on that note: artificially editing your publication date so your fic shows up at the top when you haven’t added a chapter is the dickest of moves and will make you a pariah. do not do this. yes everyone will notice.
editing existing chapters doesn’t count as updating a fic and won’t change the publication date.
ao3 usually adds weird spaces after italics if you copy and paste in your writing pre-formatted. it doesn’t add these until after you’ve saved a draft or posted so you have to re-edit.
check the “add space after paragraph” option in your word precessor of choice to avoid having to delete an extra space between all your paragraphs on ao3.
when you add a second chapter to a one chapter fic, your original start/end authors notes will now be appended onto the notes of every chapter unless you move them to the now extant first chapter notes sections. this is confusing, but you’ll see what i mean.
to post on anon: add your fic to the anonymous (anonymous) collection. it’ll take up to fifteen to minutes to show in the tag once posted. it’ll show up (to you) as AUTHOR NAME: fic title. no one else sees it this way. it will never show up on your own dashboard unless you go to your stats page. if you ever de-anon, all your subs will get an email about it as if it were just posted.
if you update multiple fics at once, ao3 will group the updates into one email.
to transfer a fic to a new ao3 account: make a new account, make the new account a co-author, remove the old account as co-author.
you cannot mention money changing hands for fic on ao3, ever. don’t say commissions. say a fic was requested if you must say anything. your fic can get taken down for this.
reply to comments or never complain about engagement in fandom.
per that: EVERY TIME YOU EDIT A COMMENT, THE AUTHOR GETS A NEW COPY OF YOUR COMMENT IN THEIR EMAIL. we can see all the edits. be aware.
tagging is both a warning and an enticement, do so accordingly. you really don’t need to tag things that fall outside that unless you want to.
on that note: please don’t do the “short fics for 300 different fandoms in one fic” thing. no one wants to scroll past that. i mean you can but it just makes it harder for people to find the thing you’ve written that they want to read.
if you are really bad at summaries just think of it as a movie tag line and don’t say you’re bad at summaries. don’t neg your own fic.
re all the questions i saw in replies: fic searches are people looking for specific fics. i don’t know what the fuck a placeholder fic is but these aren’t fanworks and you can’t post them. you can’t post discord links or rp requests or complaints about fandom. you can post fanart and meta essays. that’s allowed.