1) Download the script
2) UnRar the archive
3) Create MySQL database
4) Dump sql.sql to your database
5) Dump the following code with right details
(rs user account and pass) to same database
INSERT INTO `accounts` ( `login` , `password` ) VALUES ( 'your rapidshare login account' , 'your rapidshare password account');
6) Open up config.php
7) Edit MySQL database information
(database, user, pass) and base URL

Upload all files to *base url* (see guide
point number 7)
9) You should be fine now! Check your *base url* and test it