In mirc there are things called triggers. Triggers are a way to get into a specified folder on somebody else's computer. They look like this. !audioappz or !cablemp3 ( they usually have a ! before the word.
The first step to downloading a file is to look for a trigger. People with fserves will put up an ad describing what their fserv has, and what the trigger is.
When you type in the trigger, you will get an message saying that somebody wants to chat with you. This means that his fserv is open and you can get onto it. Click chat.
Once in the fserv, you move around much like dos...
type 'dir' to list all the files and folders this fserv has available to you...
type 'get
type 'cd
If you have any other questions, just ask somebody in #megawarez, they will be glad to help.