vpn setup for NT server4 – as client

I have an access to Internet ,want to establish a VPN connectivity to my overseas
client, I need a step to step configuarion
guidlines so that I can get connected to
my client through VPN.

I am using WIN NT 4 SEVER CONNECTED TO INTERNET THROUGH DIAL UP ISDN CONNECTION.
SO I DO NOT HAVE DEDICATED OR PUBLIC IP.