How to set up Big Wigs for boss announcements Edit
The most important plugins for a raid warner (you) are the RaidWarn and BossBlock plugins.
Navigate to the RaidWarner plugin in the menu and make sure you have the "Broadcast" and "Whisper" options checked.
Next, go to the BossBlock plugin and uncheck "Suppress RaidWarn Chat". This makes sure you can see what boss announcements you are sending to the raid warning channel for people who do not run Big Wigs. People running Big Wigs will automatically block any bossmod messages sent to this channel since they will get the same messages colorcoded in their in-game UI/HUD anyway.
In some fights, Big Wigs sends whispers (tells) to your raid members when they are affected by some things like "bombs". If you do not want to see these whispers as you send them, you can turn off "Show whispers" in the RaidWarn menu.
How to trigger custom bars for your raid Edit
Big Wigs comes prepacked with a means of starting your own custom bars in the CustomBar extra plugin. You can access it with /bwcb or through the Extras menu. Lets say you want to start a timer for a small break of 10 minutes, all you do is /bwcb 600 Break! and it will start a 10 minute timer for everyone with Big Wigs in your raid, and will give a message/raidwarn notification when the timer has expired.
How to check what version other people have Edit
Using the VersionQuery plugin, you can query the raid for what version of BigWigs your members have. This is queried on a per-zone basis, so for example querying for "Molten Core" will make everyone respond with the highest revision of any bossmod they have that is registered with that zone. You can also query for core revision with the BigWigs command.
If you do not specify any zone, the zone you're currently in will be queried for.
Remember that people do not always have to have the latest revision for things to work, please do not abuse the version query as most people do not enjoy upgrading things every day.