To get the most out of layers, ergokeyboards are used. Ergokeyboards stand for ergonomic keyboards and generally have some of the features listed:
can split apart into 2 halves
have rgb backlit keys
have tenting and can be tilted on an angle
have additional keys on the thumb region (creating a thumb cluster)
have an wrist/palm rest aligned with the keyboard
have a firmware/software to configure keyboard layers
have alternative key layouts (column staggered or ortholinear)
The main con of an ergo keyboard is that it is pricey and you have to learn touch typing properly to hit keys like b, y or 6 with the correct finger.
An ergo keyboard is not strictly necessary to create keyboard layers. I used to use layers with just software (auto hotkeys for windows | keyboard maestro for mac) and had a navigation and number layer. To do this though, I had to remap a key like the left command/alt key next to the space bar. If you have the funds and are on the computer for hours a day, I would highly recommend an ergo keyboard.
