I believe they have instructions on their site as well as to how to set it up.There are plenty of instructions here in the forum already.
What will you be using the server for? The free edition only allows up to 5 vhosts I believe, so it wouldn't do well at all for webhosting. A personal server, maybe.and is it good to install this Edition : ?
LiteSpeed Web Server Standard Edition: Free
or its better to try something els?