1) download the server software
2) make all the changes you want/need in the tsserver ini file.
3) start the server
4) start client
5) connect to the server (if you are running the client on the same computer as the server then connect to 127.0.0.1 or localhost). In case of a LAN you should know the IP adresses of your computers (ipconfig/winipcfg might help there, or go to your tcp/ip settings and figure out the ip adress there)
6) enter the Admin password and do the final setup
7) use ipconfig/winipcfg to figure out your IP address asigned to you by your ISP (unless you have a static one in which case you should already know it)
8) give that IP address to your friends and let them connect to your IP
9) In case you are behind a firewall you should make sure that tcp 8765 and udp 8766 are not blocked
10) talk
11) be happy cause it works now