You access the website editor via your OmegaOne account. Once logged into to your OmegaOne account, you will be brought to your chapter's wall.
You must have "Administrator" access to edit the chapter's website. If you have that access, you will see "Manage External Website" in the Admin Tools section of OmegaOne. Then, you will see the "Go" button which will take you to the website editor.
Once on this website editor, it will direct you to the landing page that has "Steps For Setting Up Your Website". Your editing options are on the left menu. The editing options may vary based on your inter/national organization's settings.