You need:
2 rectangles of fabric (I use fleece and a cute print), 14" wide, and as tall as you want the tunnel to be long.
EITHER foam (an inch or two smaller in all dimensions than the fabric) OR 2 11" strips of boning. I use foam in these pics.
STEP 1: Fold both rectangles in half, individually, right sides together, and sew down the long side. I use a straight stitch, and then go back with a zig-zag stitch to reinforce.
Turn the print fabric tube right side out, and, and insert it into the fleece tube, so right sides are together. Align the seams, and sew around one opening. Again, I use the straight stitch and then do a zig-zag.
Turn the whole thing right side out.
