This will come within the first 30 mins of the game and should very much be unmissable.
When you select new game you'll go right into the first mission. Just to avoid a down vote or two, I hide the exact moment behind a spoiler tag.
*** Spoiler - click to reveal ***Simply put, halfway in the mission Bob will make a giant saw, you'll hear a little joke between his son and daughter and get this achievement
If, for any reason you missed this, I'd restart your Xbox and restart the game just to be on the safe side.