I use my fingers to massage and line up the teeth edges and zipper tape slightly away from the edge. Then I use a contrasting color thread to baste the zipper into place.

I find basting the zipper to be the SECRET to a successful, even installation.

It makes it a lot easier to sew the zipper if you are not trying to control pins AND the wiggling tape while you've got the thing under the machine presser foot.

You can see how it looks from the Front-Side on the right side of the picture above.