manoise
Up Date Your Minecraft
Place the plugin into the plugin folder and restart the server.
Bucket
Yes.
java
First you install bukket, then drag the plugin into the Plugin Folder
Yes.
Make sure the plugin isn't outdated, and check what your console says.
it depends which server plugin youre using
Its a server plugin called mob disguise.
In the words of the spy: "I think not"
You'll need a plugin to do so.