After getting QMK to work, I thought it would be useful to document how I got it to work. This is starting from zero, using a Ubuntu live booting USB drive.
Hardware I’m using a basic Pro Micro dev board. It uses the ATMEGA 32u4, and supports USB natively, which is what we need. When getting these, make sure to get Micro-USB (otherwise you have the chonky mini-USB), and the 5V/16MHz version.
Setting up an Acer Aspire GX 785 desktop PC for dual-booting Microsoft Windows 10 with Ubuntu is tricky, but not impossible. If this is above your comfort-zone, just set up a VM with Ubuntu within Windows :-).
Make space on hard disk for the partitions Change BIOS security settings Create a USB disk to boot Ubuntu Install Ubuntu, creating 3 new partitions on the hard disk Fix UEFI settings Prepare empty hard disk partition In Windows, open the Disk Management tool: Right-click on Start > Disk Management Make room for Ubuntu: Mine had 2 ca 240GB partitions on the main disk.