If the title peaked your interest, then we probably don't need to fill you in on the fact that Google released an early Android N build a couple of days ago, along with a Beta program to easily receive updates over the air. If you are anything like us, then you probably ignored the bugs and stability warnings and might currently be in a situation where your phone isn't exactly 100% usable and that fact eventually managed to outweigh the Android N bragging rights. Naturally, you can always manually flash a Marshmallow build back to your handset, or any custom ROM for that matter, but if you are after a more streamlined solution, Google has you covered. The Beta program seems to work with the same ease both ways. To roll back to the latest Android Marshmallow build, you simply have to go back to same page, where you opted to participate in the Beta and click the UNENROLL DEVICE button. This will result in an OTA being send to your unit within minutes, which is also stated in the confirmation prompt. But unless you clicked it out of curiosity, you probably weren't in the know about the reverse OTA. However, be advised that any path you chose to swap Android N back to an earlier OS build will result in a restart and a data wipe. So, be sure to back everything up if you haven't...
Source: http://www.gsmarena.com/heres_how_to_roll_back_from_android_n_to_marshmallow_on_your_nexus-news-17197.php
