The forum allows users to add colours, font changes etc. to their signatures. However, html tags are required in order to customise your forum signature. The following mini-guide will show you how to decorate your signature without requiring any knowledge of html tags; all you need is a bit of patience and the features of the forum editor. Credit goes to floplot, who got this guide started in the first place :-)
1) Make sure that your settings are turned on to enable the private messaging feature. If that is the case, go to Private Messages and compose a new PM; type your signature in Rich Text mode as shown below; there is no need to fill in the required fields of the PM as you won't be sending it to anyone - you only need it to obtain the HTML tags which contain the information for colour, font etc.
2) In a new browser window or tab, navigate to any post of yours (but not to your profile page), highlight and copy your own screen name; it contains your current rank colour.
3) Paste your copied screen name into the PM you are composing. For practical reasons, leave an empty line between your signature and screen name.
4) Highlight your signature name and just add a random colour to it (I have added red in the image below).
5) Switch to HTML mode. Look at the colour code (blue highlight in the image) of your screen name. You will also see a colour code in your signature line (red box). In order to give your signature the same colour as your screen name, you have to replace the colour code of your signature line with that of your screen name. Simply highlight and copy the colour code of your screen name (blue highlight) and insert it into your signature line (red box).
Closeup and juxtaposition of the colour codes:
6) This is what your signature will look like in HTML mode after replacing the colour code. Also, delete everything underneath your signature line - you won't need it anymore.
7) This is what your signature will look like in Rich Text mode.
8) In HTML mode, highlight your signature, right-click it and copy it (I have the German version of Firefox, hence the German menu). You can discard the PM when you navigate to the signature box as outlined in step 9.
9) Paste the copied signature into your signature box.
10) Finally, scroll to the bottom of the page and click on "Save Changes". You are done! :-)