1. Find a stream running it. The streams page lists everyone playing right now.
2. Type !join in their chat. That creates your character and puts it in the world. Nothing else is needed.
3. Pick something to train with !train. Your character keeps at it whether or not you are still watching.

!join

Puts your character into the stream you are watching.

!train

Start training a skill, for example !train mining. !train all trains your combat skills together. Also answers to !task.

!stats

Your levels, and !training says what you are on now.

!raid and !dungeon

Join whatever the rest of the stream is fighting. These are the moments a stream plays together.

!village

Claim a plot in the streamer's town, which boosts one skill for everyone playing there. How much depends on your level in that skill. Also !town.

!clan

Join a clan, which shares clan skills and a level everyone contributes to.

!use

Eat or drink something from your inventory. Also !eat, !drink and !consume.

There are seventy odd commands in total and the commands page lists them. A streamer can rename or disable some, so if one does nothing, ask in chat.

• Your character keeps playing when you close the tab. It stops when the streamer stops running the game, not when you stop watching.
• Your progress follows you between streams. The same character can play on any channel running Ravenfall.
• You can play while the streamer is offline by typing in twitch.tv/popout/[channel]/chat, as long as they have left the game running.
• The website knows more than chat can tell you. Sign in and your characters page has your skills, your inventory, and which skill you are closest to levelling.

Playing needs nothing installed. Hosting it does: you run the client, your viewers type in your chat, and the official bot connects the two.