This will walk you through the basic usage of Pinafore and its major differences with the Mastodon web UI.
The home page is both where you write toots and where you read your home timeline:
When you scroll down, the "toot" button transforms into a "compose" button:
If you press this compose button, you can toot anywhere in your home timeline.
By default, the Local Timeline is pinned to the top navigation. In the "Community" section, you can view Lists, the Local Timeline, the Federated Timeline, and your Favorites, and you can also pin any of these to the top navigation.
You can manage your instances in the settings:
For each instance, you can choose a custom theme so that it's easy to remember which instance you're currently using: