I had some crochet cotton in a similar beige colour. I bravely cut the jersey down the centre, using the cable pattern to guide me in a straight line. I turned and pinned the raw edges in by about 1cm, and secured them in place with a blanket stitch. I then stitched blanket stitch around the neck edge as well as the sleeve and hem edges.
This gave me a basis for the crochet work.
It's been a lovely addition to my wardrobe and a fun artisan project for this enthusiastic novice crocheter:-)