To setup your forum signature, go to your "User CP" or "My Controls" or "Profile".

Find the link that says "Forum Profile Information" or "Edit Signature":

Once clicked, you'll see a "signature box":

You can write anything there and that text will appear on each of your posts. Some forums will have a limit on how long your text can be and when you setup a long text or code, you'll get some error message. Also, be sure to comply with the forum rules on signatures as they usually tell you the number of lines your signature can have or a rule regarding banner images. You can also choose to have a link, rather than just plain text on your signature which would direct those who click on it to the site on the link. You can even embed images on your signatures.

To setup a text link on your forum signature, enclose your desired text with the "[url] [/url]" tag.
The code will look like this:

[url=http://www.yourlinkhere.com] Your Text Here [/url]

Example:

[url=http://yourlinkhere.com]The Online Earning Arena [/url]

The Online Earning Arena

To put colors in your forum signature, enclose the text with the "[color][/color]" tag.
The code will look like this:

[url=http://www.yourlinkhere.com][color=#color] Your Text Here [/color] [/url]

Replace the #color part (without the "#") with a basic color name e "green", "red", "blue","yellow", etc.
Example: [url=urlname][color=blue]Text[/color][/url]

Or you can use the hex code for colors:

Example:

[url=http://yourlinkhere.com][color=#F34411]The Online Earning Arena[/color][/url]

Result:

The Online Earning Arena

To make your text signature bold or italic, enclose the text with [b][/b] for bold or [i][/i] for italic.
The code template would look like this:

[url=http://yourlinkhere.com][color=#color][b] Your Text Here [/b][/color][/url]

Example:

[url=http://sitename.com][color=#F34411][b]Your Text Here[/b][/color][/url]

Your Text Here

To setup your signature with a banner image, the code template would look like this: [url=http://yoursitename.com][img="banner image source"][/img][/url]

Replace "yoursitename.com" with the link to where you want to direct users to when they click on your banner image. Replace the "banner image source" with the link of where your image is located or stored.

Example:

[url="http://www.evolutioniscoming.com/EVO172835JA"][img src="http://www.evolutioniscoming.com/flash_tools/468x60-evo.gif" width="468" height="60">[/img][/url]

Result:

The standard size for banner images on forums is usually 468 by 60. But you can choose to omit the "height" and "width" attributes above if you don't want to specify the banner size.