I showed you how to download the macOS installer through the Mojave Mac App store. The thing is, a better way to download the full installer exists and is called installinstallmacos.py. I was going to explain how to use installinstallmacos.py here but now realize the topic deserves a full article. I did not even get into hardware specific (Forked) builds. As you can see we have a lot to go over, so stay tuned. I will put the link here when complete.