Why you complain about buggy experimental unstable ROMs? You are nor forced to use it. You can use stable ROM if you get emotionally triggered by bugs.
On your phone, under Developer options, have USB debugging and USB debugging (Security settings) switched on.
You do not have to go into Fastboot or Recovery - just have the phone running normally.
Connect your computer to your phone.
In the adb folder on your computer, run the command prompt.
First, run 'adb devices' to make sure that the connection is correct.
(The result should be a code and 'device').
Then run the adb commands. 'Success' should be the result of each command.