If you want to create a thread on Mastodon or other Fediverse platforms:
1. Publish the first part of the thread as a post
2. Reply to your post with the second part
3. Reply to your previous reply with the third part etc.
More info and questions answered at:
https://fedi.tips/how-do-i-post-a-thread-on-mastodon
Some mark their threads with a symbol and/or number the thread "1/5" or "1/X" so people can keep track of which page they are on.
To see the thread that a post comes from, just click on the post.
@FediTips Eh? Reply to your own reply? For real? I remember doing that once back when forums were a thing. Folks were laughing at me.
@adrianmorales@ieji.de Posts on forums usually don't have a character limit.
@FediTips@social.growyourown.services
Just to add, there is no official way for owners to set the character limit on vanilla Mastodon, it's hardcoded to 500.
The only way Masto instances can change this is if the owners alter the code, or if they install a fork like Glitch or Hometown.