HOW INSTALL WHMCS Wordpress Integration ?

HELLO
i want Integrate WORDPRESS with WHMCS !
my main website :
http://fnxsabt.com
my whmcs address :
http://user.fnxshipping.com
this 2 site are locate in different server and domain !
now i can locate main page inside whmcs with this adress
http://fnxsabt.com/?page_id=276
but for another page show page not fond !
like this :
http://fnxsabt.com/https://user.fnxshipping.com/clientarea.php/?

how i can fix this ?