For a more solid effect - Make a copy and move it slightly behind the original. Use "Mesh/Reverse Surface" to flip it (you can turn off Double Sides to check its real orientation). Then select both meshes "Mesh/Join" and "Mesh/Stitch Holes" to stitch the two parts together. The seam is left selected for easy smoothing (Press 'S').
For the little holes near the cord I again used Mask and Delete to make little holes in the mesh and used "Mesh/Stitch Holes" to seal the mesh back together.