How to create Symbol groups
To group Symbols together in the Components View and Insert menu, name them using the format: Group-name/Symbol-name. For example, two Symbols named Button/Normal and Button/Pressed will become part of a group named Button.
Note: You will need to have two or more Symbols in a group before they’ll appear in their own submenu.
Organizing Symbols in the Components View
You can also organize your Symbols via the Components View 
. To group several styles together hold ⌘ and select the Symbols you want to group. Control-click on any of the Symbols, and choose Group in the contextual menu. Give a name to the new group by double-clicking on the new group 
that you‘ll find in the left sidebar of the Components View.
To rename a single Symbol, click on the Symbol and rename it using the Inspector. To rename a group, double click on the group name in the left sidebar and add a new name to the group.
You can also add a Symbol to an existing group by dragging it to the left sidebar to any of the groups you already have.
Symbols in the Components View are ordered alphabetically.
Using the Symbols page
Sending Symbol Sources to the Symbols page can help keep things organized, especially with complex designs. It also helps to reduce confusion between using a Symbol Source or instance.
To manually move a Symbol Source, drag it onto the Symbols page title in the Layer List, or Control-click on it and choose Send to “Symbols” Page.
