Always use HTML tags to create lists.

Lists are used frequently to organize and depict related information. It is important to ensure that your lists are accessible to all users. Using dashes or bullets may look like a list, but will not be portrayed as one to those using assistive technology–make sure to use the list block to create lists.

Always use the <ol> tag for numbered (ordered) lists, and the <ul> tag for bulleted (unordered) lists. Use unordered lists when the order information is portrayed does not matter, and ordered lists when the information should be portrayed in a specific sequence. Use the indentation button to nest items under one another.

GUWordPress will create these tags for you if you click one of these icons in the editor:

Ordered and unordered lists buttons in the Drupal interface