Anyone is able to use the public toolbars listed on the website. Simply select the desired toolbar and drag the install bookmark to your bookmarks bar. When you are on any web page, select the toolbar bookmark and the toolbar will load.
If you would like to create your own toolbars, customising the plugins installed, you must be registered. Once registered, select any number of plugins and a toolbar name. You should name the toolbar relevant to what it includes and provide a suitable description. Toolbars, like plugins, have tags used for searching. You should select a suitable number of tags which reflect the toolbar. If a tag you want is not listed new ones can be added by entering them when authoring a toolbar.
Just like public toolbars, drag the install bookmark to your bookmarks bar to use the toolbar on any webpage.
Further questions may be answered by the FAQ page.