Bookmarking is a great way to save a line of code so that you can navigate back to it later or cycle among all of your bookmarks.
You can use the following methods to bookmark a line:
From the menu, select Navigation | Add Bookmark and Navigation | Remove Bookmark.
The keyboard shortcut Command + F2
Click on the gutter next to the line in order to toggle the bookmark:
A star indicator in the gutter signifies when a line has been bookmarked.
The Next Bookmark option is used to go to the next bookmark in the document. From the menu, select Navigation | Next Bookmark (F2).
The Previous Bookmark option is used to go the previous bookmark in the document. From the menu, select Navigation | Previous Bookmark (Shift + F2).