Sometimes all of us need to make a graphical installer for one's own linux distro. It goes without saying that you are able to use a distro-specific installer like Anaconda for RedHat-based or DebianInstaller for debian-based. On the other hand Calamares is a graphical installer which is not aligned with only one package manager.
I want to share my experience how to make a universal install solution with GUI. I did not find any complete article about it, hence, I reinvented the wheel.