Install tomcat 7 and MongoDB on your server. You can simply copy the locsy.war file into tomcats webapps directory and it will be deployed automatically. You need to add a Locsy admin user to your tomcat-users.xml file:
<tomcat-users>
<user username="user" password="password" roles="locsyAdmin" />
</tomcat-users>
After you've done all this you can simply go to the url yourserver.com/locsy/settings.xhtml and add new users to your Locsy installation.