A cable railing assembly having a plurality of posts, an expandable cable guide assembly, and a tensioning apparatus, and a method of assembling the cable railing assembly. The expandable cable guide assembly includes a pair of cable braces with a cable extending in a serpentine fashion between the cable braces. The tensioning apparatus includes a tensioner base, a tensioner body, a compression spring positioned between the tensioner base and the tensioner body, a movable carriage slidably mounted adjacent the tensioner body and comprising a cable clamp for gripping the cable, and a threaded adjuster secured to the body and operative for moving the movable carriage along the body.