www.eda.co.uk

PCB Layer Sets are a new feature, added to Altium Designer 6 in the 6.3 update, which allow you to toggle your workspace to display different sets of layers.
By default there are 5 layer sets defined to allow you to view All Layers, Signal Layers, Plane Layers, Non Signal Layers or Mechanical Layers.

Layer sets can be activated from the menu Design » Manage Layer Sets by selecting from the list, e.g. All Layers, or from the button to the bottom left of your workspace.

Layer sets can be edited and defined with in the Layer Sets Manager, which can be found under Design » Manage Layer Sets » Board Layer Sets.

Within the Layer Sets Manager dialog you can create new layer sets, either from currently visible layers on your PCB or by creating an empty set and selecting the layers you wish to include.  You can change the Active Layer by selecting and the left mouse clicking to produce a combo box.  The & symbol in the set name is used to signify the following character as an accelerator key. 

For example D,T,S accelerator keys will select Design » Manage Layer Sets » Signal Layers.  

If you wish you can customise shortcut keys to directly access your layer sets.  To do so you need to customise the menu item, for example, select Signal Layers from the menu or the button whilst holding Ctrl to open the Edit Command dialog box for that command.  At the bottom of the Edit Command dialog box you can setup shortcuts.