To start submitting you first have to Install the Form Filler (You need firefox) To install just download the file and then drag and drop it onto firefox
and then fill in the information for your site bellow.

In the category suggestions you should fill in your most relevant categories in 1 & 2 and have something general in 3.
For example if you have an arcade site: 1 arcade game, 2 online game, 3 game

 Your Name:  Mail:  Category Suggestions: 1 2 3
 URL:  Site Title:  Description:  

Here are the directories you can submit to when you have done the steps above.