To attach the zipper to the leather place your leather on the table with the good side facing up. Then clamp the zipper to the leather with the good side of the leather against the top side of the zipper.
Sew zipper to the leather.
Then fold over the leather so that the good side of the leather and the top side of the zipper are facing up .
Sew across the leather to fasten the leather to the zipper. This seam will be visible so try and keep it straight.
Now to attach the other end of the leather to the zipper in the same way. Good side of leather to the top of the zipper sew together. Then fold over the leather and sew this last seam across , remember this seam will be seen.
I actually turned this project outside right to make the last seam and then folded it inside out again for the rest of the project.
Fold the project in half so that the zipper is in the exact middle of the material .