How do i join the insider 365 program?

I would like to know how to participate in this program. I am spending most of my day inside of 365 and have quite a bit of insight on what small businesses can leverage on 365.

i have followed instructions:
File--> Account and then look on the right side of the screen to see what Channel you are in. You'll look at the "About" button and see a Build number and version and then you'll see a channel. If you don't see "Beta Channel" or "Current Channel (Preview)", then you're not an Insider (yet).

I am currently not setup.