First, create the [Build Environment](doc/qubes-r3-building/) (follow the build environment section only).
Next, configure the builder:
~~~
cd ~/qubes-builder
./setup
# Select Yes to add Qubes Master Signing Key
# Select Yes to add Qubes OS Signing Key
# Select 3.2 or 4.0 for version
# Stable
# Yes (we want to build only templates)
# Select builder-fedora, builder-debian, template-whonix, mgmt-salt (builder will complain if you don't include builder-fedora, but we don't actually use it)