Help

How do I get certain plugins to work such as one that checks email and one that checks to see if your online? I don't have any idea how to configure it and the tutorials I've seen so far are beyond sketchy on just about everything. btw I have the info for my pop3 server and all that put in to the mail checker but it says I have to add custom messages and I don't know exactly what TO add. Someone please gimme some imput