I am a big fan of invisible zippers in my sewing. Truth be told, I have never installed a regular zipper--I went from complete zipper ignorance to the three dollar plastic invisible zipper foot I am using now.
My biggest zipper challenge is always to install it evenly from the top so that my left and right waist seams match perfectly. I have tried basting, with only moderate success. My hand stitches are not enough like the tight machine stitching to ensure that the two sides of the zipper are going to end up that same distance down from the top of the dress, like they promised during basting.
Here's what I hit upon in the last dress I made (see Clara playing her cello in the coral corduroy, above): I sew the zipper in on one side. Then, counter to all the instructions I have read which order me under pain of death to not zip the zipper up until both sides have been sewn in, I zip it up and use a pencil to *mark where the waist seam should hit*. Then all I have to do is move heaven and earth to make sure that little pencil mark lands on the waist seam. Easy as pie! Or easier than it used to be.
Now that I have this nailed I'm going to miss all the ribbons-stitched-around-the-waist styles I have made in the past to cover up my mismatched waist seams.