1. If you go to the very top of the screen (where the logout button and such is), if you're on the community page, there's a link that says post somewhere near the center (not the one next to the home link). That will let you post directly to the community.
2. If you go to the community profile, on the far right, upper side of the screen, there's a link that says, "Post to community."
Re: B2MeM 2019
There's a couple of ways to post to the B2MeM community. (Please make sure you follow the posting format and tagging rules.)
1. If you go to the very top of the screen (where the logout button and such is), if you're on the community page, there's a link that says post somewhere near the center (not the one next to the home link). That will let you post directly to the community.
2. If you go to the community profile, on the far right, upper side of the screen, there's a link that says, "Post to community."
Welcome to Dreamwidth, too! I have a bunch of Tumblr-to-Dreamwidth guides on my journal if you want to peruse them.