Get a piece of felt.
(It doesn't really matter what colour you use,I used black to keep it looking authentic)

Cut the felt into a rectangle.(I cut mine 9cm x 5cm).

Fold the piece of felt in half.

Cut a piece of wire roughly twice the length of the rectangle.

Slide the wire in between the fold like so.

And either machine stitch or hand stitch(I used a blanket stitch) around all the edges till secure.

Bend one end of the wire into a spiral shape(thats what I did)or till secure.

And do the same on the other end of the wire.

Now your ready for the stitching.

With the white embroidery thread,either machine stitch or hand sew 2 long lines,parallel to each other.
(I did machine stitching to speed up the process)

Then stitch 2 small lines on either side of the rectangle as pictured.
(I handstitched these lines since they were much smaller)

Next,stitch a line through the middle(i machine stitched)

Sew a very small stitch near the centre of the middle line,to represent playing ball.

At the top,stitch score numbers.

Lastly,thread a long piece of ribbon through one of the holes and knot off the other end through the other hole,then your done!

Enjoy :]