Click on the SIGNATURE OF THE WEEK link in the upper right part of any window.

Then, under the heading SYSTEM LINKS, click on SUBMIT AN ENTRY.

You will then be asked to submit the URL to your image.
This is the DIRECT LINK URL to your image. It does NOT have [img][/img] tags.
Your image URL needs to be short and cannot contain any special characters such as spaces or symbols.
eg
CODE
http://www.myimagesite.com/sotw/myimage.jpg
NOT
CODE
http://www.myimagesite.com/images/myalbum/sigs/darkside/mysigs/sotw/myimage.jpg
Therefore you will need to upload your image to the main folder of your image host or very close to it.
**Extra note:- If you are using Image Shack as your image host beware of their new image tags. The default direct link tag is a link to the THUMBNAIL of your image rather than the image itself.
You will be able to tell if you have the right link or not by looking at the end of the URL. If it says ...myimage.th.jpg, it is a thumbnail. Simply remove the .th and you are good to go.
The winning entry will be rehosted on our Darkside server, so there's no more chance of running out of imagehost's bandwidth by winning the competition