Creating the Hierarchy
The top stem of your branch has a handle which allows you to connect the entire branch to a parent shape or tree. For your branch to connect to something else, you must have the Allow Lines to Link setting turned on under the Arrange menu. (It should be on by default.)
Position your branch below the home page, then grab the grow handle and stretch it until it attaches to the link points of the object above.
Once the branch is attached, you can close the space between the home page and the branch by clicking and dragging the grow handle located at the intersection of the main stem and the main line.
Learn more about grow handles here.
Continue building the hierarchy until your map is complete.