A post goes to a group's Wall and to the people in it. Use it for the things everyone needs to read — a fixture change, a kit order, a season plan — rather than for a conversation, which is what chat is for.
Write a post
Open the group, then Posts. On a phone, use Create and pick Post.
Click New post.
Write the body. This is the only required part — the title is optional, and the field says so.
Add Attachments if you need them. Pasting a YouTube link into the body embeds the video.
Click Preview to see it as your readers will, then Publish.
Posting to more than one group at a time adds a step: the button reads Select groups instead of Preview, and you pick the groups before previewing.
Choose who it goes to
A tab switcher at the top of the form sets the scope. Which tabs you get depends on where you are.
Team post — this group only. Always available.
Multi group — this group and any of its subgroups. Appears when the group has subgroups.
Club lobby — the whole club, including people not in any team. Only at the top level of the organization.
Advanced settings
Everything else lives behind Advanced settings, collapsed by default. Admins and staff see it; a player writing to their own team does not.
Send as — post as the group rather than as yourself, so club announcements are not signed with one person's name.
Visibility options — who on the Wall can see it: Players ("Players will see this post on the wall."), Parents ("Parents will see this post on the wall."), Admin and staff ("Admin and staff will be able to see this post"), or Public. A Club lobby post has no visibility options — it goes to everyone by definition.
Sticky post — pins it to the top of the Wall until a date you set.
Comments enabled — "Recipients will be able to comment on this post". Turn it off for anything that should not become a thread.
Notify recipients — sends a notification as well as putting it on the Wall.
Schedule — Publish at a future time. Left alone, "The post will be visible instantly."; scheduled, the publish button reads Schedule and the post sits as Scheduled until then.
Edit, delete, or find an old post
The Posts screen lists everything the group has published, with Status — Published, Scheduled or Draft — and a filter by title or content.
Open a post's three-dots menu for Edit or Delete. Editing a published post updates it in place; it does not re-notify anyone.
Who can post
Admins, staff and players can write posts. Parents can read and interact with them but not create them. The advanced settings above are admin and staff only, so a player's post goes out with the defaults.
Troubleshooting
Publish is greyed out. The body is empty, or an attachment is still uploading. The title being empty is fine.
Nobody was notified. Notify recipients is a setting, not the default — it lives under Advanced settings.
Parents cannot see it. Check Visibility options. Players and parents are separate switches.
No Club lobby tab. You are in a team. Switch to the top level of the club.