Now to make a zipper sandwich. Place 1 piece of lining fabric down horizontally, right side facing up, then the zipper, face up centrally along top edge, then your outer fabric horizontally, right side facing down. Line up the three edges and pin to secure.
Roughly tack zip into place with needle and thread.
Using your sewing machine with zipper foot, sew across top between the edge of the zipper sandwich and the zipper teeth (closer to zipper teeth). Repeat on other side with other 2 pieces.
Remove tacking. Bring wrong side of outer fabric to wrong side of lining fabric and top stitch along each side of zipper to neaten up.
Next, bring both pieces of lining fabric to one side and both pieces of outer fabric to the other.
Unzip zipper all the way and lay zipper ends on top of eachother, teeth toward lining side. Pin to secure.
Sew all the way around outer side leaving 1cm seam allowance, making sure you sew outside of the metal parts on each end of zipper. Repeat with lining side but leave a 2” opening on bottom edge.
Remove pins and turn right side out. Stitch opening closed by machine, or slip stitch by hand, and push lining inside.