1. Post in thread
2. Browser redirects to view your post automatically
3. See number at the end of URL. This is your post number.
4. Edit post, insert number from the URL.
Alternate Way:
1. Edit post
2. URL will show post number near the end
3. Copypaste number into post and hit save.
First person to get dubs gets a crappily drawn gif avatar.
First person to get 666 is proclaimed King of JFF.