If you are a Family Tree Builder user, please check out the following FAQ: How do I sync my tree?
If you already have a family tree on your family site and you’d like to add a new one, log into your family site and from the Family Tree tab, select Manage trees. On the right side, just above the list of trees, use the link Add Family Tree.
In the next page there are four options to allow you to choose the type of tree you’d like to add.
1. I don’t have a genealogy program yet (lets you download our family tree software, Family Tree Builder, to create your tree)
2. I have Family Tree Builder by MyHeritage.com (tells you how to sync your tree from Family Tree Builder)
3. I already created a family tree on another genealogy program (lets you import a GEDCOM file)
4. I want to create an online family tree, without the use of a genealogy program (starts a new online tree you can start working on directly on your family site)