To add a tag, click the + button. A sheet appears that allows you give the tag a name and enter the start and end parts of the tag.
The closing part is optionalŃyou can use this feature for bits of text you type frequently. ItŐs not just for custom HTML tags.
Pull down the HTML menu in the toolbar and choose Edit Shortcuts.
The shortcuts editor window appears. It allows you to edit the shortcuts for both the built-in HTML tags (in the HTML menu) and your own Custom Tags.
Click the triangle next to HTML or Custom to expand it. Select the item whose shortcut you want to set, then click the Edit button. A sheet appears that lets you edit the shortcut.
You can also Reset an individual item or Reset All shortcuts.