Here are the FAQs in their entirety, with the sections needing emphasis in bold (add emphasis in any way you like :)
First of all, as the community's maintainer, you don't have to do anything if you created the community using the "Open Membership" option with posting access given to "All Members". Those options allow any LiveJournal user to obtain membership and posting access in your community, by joining it without seeking your approval.
To elaborate on that: when you create a community, you decide whether membership will be open or closed, and whether all members will have posting access. (See http://www.livejournal.com/support/faqbrowse.bml?faqid=79 .) If later you change your mind about how those options should be set, you need to go back to http://www.livejournal.com/community/create.bml and re-create the community using new settings. Enter the relevant maintainer and community usernames and passwords, choose the new level of access, and then click "Create Community". (The community's journal, Friends list, etc., will not be destroyed; only the settings you enter differently will be changed.)
On the other hand, if you've deliberately made your community a closed community, or you don't allow all of your members to post, then you can grant individual users access to your community by going to the Administration Console, located at:
There are two commands regarding communities and membership; "community" and "shared". The "community" command, when used properly, can easily upgrade people to being a member of a community. The "shared" command allows certain users posting access to a community, if the posting access rule is selective.
Before visiting the console, make sure that you are logged in. Remember that only the maintainer of a community can use the commands in the console area.
Commands are entered as single words on a line, with no brackets. Brackets you see here are for reference purposes only. Words in angle brackets represent required arguments to ensure the command works.
Adding A User To A Closed Community:
The command for adding a user to a closed community would be:
community = the initial command
So, for example, to add the user 'test' to my community named 'communitytest', the command would be as follows:
community communitytest add test
Allowing A User Posting Access To A Community:
In the same manner, if you wanted to allow someone to post in your community, the command would be:
shared = the initial command
And the example command to allow the user 'test' to post in the community 'communitytest' would be:
shared communitytest add test
Yes and no. The maintainer of a community is the only person allowed to remove and ban people from that community.
A maintainer can remove a member by simply removing that member from the community account's friends list. If need be, the maintainer can log in and then ban a user through the /admin/console ( http://www.livejournal.com/admin/console ), although that will only ban the user's comments. In a closed community, a member may be removed by using the commands listed above in the section on the /admin/console.
Be aware that at this time, the ban_set command described below only prevents the person from commenting in a community; if he is a member in an open community, for example, he will still be able to post.
Banning A User From A Community:
The command for banning a user from a community would be:
ban_set = the initial command
So, to ban blueglass from commenting in my "test" community, the command would follow:
ban_set blueglass from test
To remove the ban from a user would entail:
ban_unset = the initial command