Since the board is getting flooded with threads asking for help with sigs, I decided to post this so every new member learns how to do it.

First, when you create an account and you log in, you'll see in the upper left corner of your screen a little box which indicates if you have any new PM (Personal Message) in your Inbox and how many users are online at the moment and how many of those are in your buddy list (if you have any).
Look below the box and click where it says "Settings", it will take you to the Settings page where you can change your avatar (little picture that appears in every post you make), your signature and your account password. It appears in that order.
There, where it says "Signature" and "HTML Allowed" is a space, there's where you write whatever you want for a signature. You can write whatever you want there. Also, you can put links and images using HTML. Since you can't advertice your own site or forum on MKO's forums with a post, you can do it on your sig.
For puting a link, you need to put the HTML code which is:
&lta href= URL HERE&gtTEXT HERE&lt/a&gt .
For putting a picture, the code is:
&ltimg src="URL OF PIC HERE"&gt .
When you create your signature, you will be able to see it in the preview box. If you're happy with what you see, scroll down and click no the button that says Submit and you'll be done.
For more help with HTML codes, click here.

The MKO forums has some rules about stuff that can and can't be put on the sigs. To learn more about the rules of the forums, go to the MKO FAQ.