Of course, you can also use your computer keyboard to control your key switches. As for a MIDI controller with pads, you have two options here again.
You can use the key map mode to assign individual keys to the blue numbered buttons of the key switches to exclusively control a single instance of the KeySwitch & Expression Map or to switch multiple instances at the same time.
To do this, press the Key button in the upper right corner of the Ableton user interface (1), select one of the blue buttons with the mouse (2), and then press a key on your computer keyboard (3). Now you can see the numbers or letters of the keys with the numbers of the key switches in the Mapping Browser. When you are done, press Key again to close the Mapping Browser (4).
If you want to operate your key switches this way in Ableton 10, you have to make sure that the small piano button is disabled and greyed out. Otherwise, the letters listed below are part of the Computer MIDI Keyboard and are reserved for playing notes only. The piano has priority!
In Ableton 11 this has been changed and both will be triggered. However, this is indicated by red buttons to draw your attention to possible conflicts. In our case, this would indeed lead to problems. As soon as you actually play another instrument with the Computer MIDI Keyboard the KeySwitch & Expression Map would then also react each time – most probably in an unintended way.
In addition, some keys like Q (Toggle Hot-Swap-Mode), D (Toggle Drum Rack), U (Unfold Selected Tracks) etc. are assigned to keyboard commands. If needed, find here a list with all keyboard shortcuts in Ableton. In this case, your manual mapping takes precedence, but you can no longer work with the shortcuts.
Particularly unfortunate is actually also the assignment of numbers with key mappings, since you can then no longer enter values in Ableton. All in all, this is a good option for a live gig, but not really practical for composing.
It is actually better to use the notes of the Computer MIDI Keyboard. This way you can switch between 15 key switches (without having to change octaves) and always control only the instance of the KeySwitch & Expression Map whose track is currently armed. Small labels with the articulation on the keys, could be an additional help if you like.
Please note that you can only use the Computer MIDI Keyboard together with a real keyboard if you have MIDI From set to All Ins. If your live set-up does not allow this, you can alternatively create an additional track for the KeySwitch & Expression Map that only listens exclusively to the input of the Computer MIDI Keyboard and sends then the parameters of your key switches directly to the instrument of the other track. But having two tracks for your instrument, unfortunately, dynamic arming of the tracks becomes more complicated 🙁