Configure AlwaysOn backups
I am running Availability Groups and using Ola's backup solution, and here is how I have it set up:


First, Availability Groups do not do their own backups, something has to be scheduled to run a backup.  So make sure there is not a Maintenance Plan already doing backups on the SQL Server
Make sure Ola's scripts are installed and up to date on all of your Availability Group servers. :)
Create a SQL Agent job for your FULL backups that calls Ola's dbo.DatabaseBackup procedure; schedule this to run however often you need.
Repeat step 3 for your DIFF and LOG backups.
Copy the backup jobs you just created to all of your secondary Availability Group servers.


Here's what you need to know about Ola's scripts:


They are what I like to refer to as "Availability Group Aware", meaning that you can run the same backup jobs on both your Primary and Secondary AG servers, and they will act accordingly. (ex: If you run a FULL backup on a Secondary, Ola's script will recognize it is on a secondary and exit gracefully without doing anything)
If you specify ALL_AVAILABILITY_GROUPS as your backup database, it will backup only the databases in ALL of the availability groups on that server. If you specify USER_DATABASES, it will back up ALL user databases on the server (including the ones in the AG).