The next version of macOS is called Catalina and today its first public beta version was released. This means that anyone with a Mac can try the beta version of the next operating system. Also, you don't need a Apple developer account. This is how you can install the new version of macOS Catalina.
Install macOS Catalina
If you are not following this on your Mac, search for your device before continuing. Also, it is a good idea to make a backup of your first files, just in case. Needless to say, this is a beta software and things can go wrong.
Visit the page: https://beta.apple.com/sp/betaprogram/ with the Apple ID you use on your Mac.
Once you are logged in, you must register your Mac in the program. You must click on the link to continue.
Now, on the next page, click on the "Download macOS public beta access utility" button and a package will be downloaded.
Find it in the "Downloads" folder and proceed to install it. Thus, the package will advise you to make a backup of your Mac if it does not detect a Time Machine. It will also tell you that an application called “Feedback Assistant” will be installed on your Mac. There is no way to prevent the installation of this application.
Also, the package will be installed in a few seconds and the Feedback Assistant application will start. Switch to this application first and accept the agreement on the screen. In the background, the Software Update will run and look for an update. But if you have not accepted the agreement on the Feedback Assistant application, this will fail.
Follow these steps and you will have the functional operating system
Once you have set up the Feedback Assistant application, look for a software update in the same way that you update macOS.
Now, when you have detected the update, you can download and install it. Again, it will be installed like any other macOS update.
Similarly, the beta version of macOS Catalina is updated at this time. Many times, it happens that they try to access this operating system and sometimes it tells you that it is being updated. Eventually, you will get the public beta access utility, but Catalina download through macOS will be slow. It is a good idea to wait a couple of days to get that update.
Also, the update is not permanent, that is, you can return to the stable version of macOS Mojave. Once you have the macOS Catalina beta version installed, you will continue to get the other beta versions that are released.
Beta versions are normally a version behind developer compilations. However, you will get each beta version released before the final stable version and all previous public versions.