How often should the SP2013 Admin check the health of the servers?

Although I’ve been using SharePoint for 6 years, I’ve not had any Administration training.  I’m trying to determine how frequently I should be going in to review the health of the servers in my farms (one dev farm, one production farm).

Is there a “best practice” concerning checking and maintaining servers?

I’m trying to figure out how I often I should be doing things to prevent issues and to write documentation of what my job entails (I’m the admin, the user support, the developer, the designer for our organization).

I’d be interested to hear the suggestions/guidelines from the community.