Phone help? (android)

Since I loved Glitch and it shut down I decided to get some ringtones from the "Downloads" section and put them in my phone.

I already made a ringtone and I'm happy with it, but what I need is putting in a new notification sound. I know where the settings are and everything. The notification sound is in the "Sounds" file and it's a second long (so it's not too long).

So basically, how do you make your sound appear in the notifications menu when you choose a notification sound?

Sorry if I sound too confusing.