How to manage size in SQLServer 2012

I am running out of disk space in SQLServer2012 running as a SharePoint 2013 repository. I though I setup limits during the setup of SharePoint 2013 and SQLserver2012. On the SQL server management studio I see SQLServer logs current and 6 archives. There are only a few users of SharePoint now and mostly calendar & task lists.

Howl do I set the server to limit the size. I appreciate any help.

John Lenz