Upgrading Roamio Basic with used 3TB drive (format?)

Hi all, I just got the Roamio basic and got a WD 3TB drive on eBay that was previously used for a few days on the persons Roamio. However, they didn't erase or format the drive before sending to me. I believe they had recorded a handful of shows.

What are the steps I need to take before I install this, I'm not too versed in formatting a drive when it comes to Tivo use and don't want to screw anything up.

Thanks for any help!
joe