CAD tip # 6982:

In the CUI dialog first create (see the "New command" icon") new commands (menu macros) in the form of:

  
'_-LAYER;_Set;mylayer1;;  

Then assign keyboard accelerators to these newly created commands. In the section Keyboard shortcuts > Shortcut keys attach the required key combination ("accelerator", "hotkey"): first mouse-drag the command from the list of commands to the above mentioned section and then on the right side fill in the field Keys (good candidates for key combinations for a series of layers are e.g. Ctrl+NumPad0 to 9, Alt+NumPad0 to 9, Ctrl+Alt+NumPad0 to 9).

After you exit the CUI dialog you can quickly switch your layers from the keyboard, just by a simple key combination.

Another option for incremental browsing through layers or blocks using arrow keys or PgDn/PgUp is enabling the name search in the AutoCAD command line - see the Browse layers video how to cycle through layers (it is in Czech, so for EN version type Layer instead of Hladina and Block instead of Blok):

You can also just start typing the layer name - the autocomplete feature will propose the matching layer.