Lauraflorafoot

I find that invisible zippers are the easiest to put in neatly. In fact, I almost always use an invisible zipper. The only place I haven't lately is in reconstructing the pattern on some existing pants for a customer of mine, which pants have a regular zipper that goes up to the top of the wide waistband (usually the zip stops at the bottom of the waist band, which is then buttoned or snapped, etc.)
When I stitch the bottom part of the zipper, where you are supposed to pull the zipper tape to one side and then put the needle in " a little above and 1/8" to the side of the last stitches" , I make that 1/8" smaller and put the needle in more like 1/16" or just a hair's breadth away from the last stitches. That way, on the right side, it does not have a gap or a bump. When I pull the tape to one side, after lowering the needle in-to hold it in place before starting to sew- I ease off on the tape so it does not distort the fabric. Positioning the needle correctly and carefully is most important. Also try a quill or long needle to help you push it in place before you start sewing, since you can't get your fingers under the presser foot. It['s a little finicky, but it works well.