How to use the Expeditor toolkit 6.1.2 with Notes 8.5 beta

I’ve heard the question a couple of times recently how to use the Expeditor toolkit with the Notes 8.5 beta. I’ve seen some instructions from external bloggers how to set up the Eclipse IDE for Notes 8.5 (for example from Mikkel Heisterberg). My colleague Pierre Carlson has posted instructions for how to use the 6.1.2 toolkit before the 6.2 toolkit will be released.