The program can be downloaded for several sites. Check the home site of mIRC at http://www.mirc.com.
While installing remember that you probably don’t want a lot of strangers to know your e-mail adres. So when asked to enter a mail adres, use a address that could exist for example me@here.com. Also in the screen where you have to fill in a ‘nick name’ it would be wise to think about the consequences of using it.
When the program is installed, it has to be configured so that you can receive de files that you want. This is done with a mechanism called XDCC. Here a few screenshot of me that show how my mIRC is configured. The options are configured by the pull-down menu ‘File->Options’. Please be sure to use another nickname, else you will have to change it when I'm allready online.
Local Info will be configured automaticly, don't enter any data, it's a waste of time.
The most important part starts here:
In the next options section you have to configure where your downloaded files are saved. Click ‘Edit’ and a screen will give you the possibility to changes the directory.
Now the mIRC is installed and configured. Now the next step. The 'how it works' part.