First, unless this is only a hobby site, you do not want to run it on your desktop PC; you need a dedicated PC/server.
Second, you must check to see if your Internet provider allows servers, of if they are blocked.
Third, you need to determine how your DNS will work. If you have a static IP address you can simply use the DNS service that came with the domain, but if it not then you also need a service like Dynamic DNS.
Fourth, you will need to decide what type of server software you want to run.
Fifth, configure your server to use no more than 80% of your UPLOAD bandwidth, because if your upload gets saturated it will kill your download speed.