What this page is
Write a campaign: pick the channels, the audience and the message.
Compose is a tab in Your Brand. It has its own address, /compose, so it can be bookmarked or sent to somebody directly rather than described as a series of clicks.
A look at it
A walkthrough of this screen — what is on it and what each control does — is being written. Until then the page itself is one click away.
Compose
/compose