Bookmarks can be used to create incremental links within a topic. The Bookmark icon appears next to the bookmarked objects. To view bookmarks from the Project.
Manager, click on the plus sign 
next to a topic.
Create Bookmarks
Click on the left of the desired location for the bookmark in the Design Editor. Then click the Insert Bookmark icon from the Links section of the Insert tab. Enter a name, without spaces, using any combination of letters and numbers.
After you save the topic, bookmark icons appear indented under topics listed in the Project Manager pod and next to topics in the Topics List pod.
Rename Bookmarks
Open the topic with a bookmark. Double-click the bookmark next to the topic, edit the name, and then click OK.