Select Snippet from the Component type drop down list and click the Add new Component or Add another Component button.
Select the Snippet type you are trying to add.
Add code to the Snippet text box in the necessary format as required by the chosen Snippet type.
Things worth mentioning
If you find that you need to add a Snippet type, but don't already know required formatting of the Snippet, submit an indicating the page you are trying to add the Snippet component to, the Snippet type and the any code you may have for the Snippet.