A few tips for working Kitchener:
1. Hold your right-pointing knitting needles as close together as you can get them and snug your stitches up firmly as you go. Otherwise, your Kitchener row will be too loose and when your join is finished you'll have to go back and coax all the gaping stitches into proper alignment with a tapestry needle.
If you can get your left index finger between the two parallel knitting needles, your Kitchener stitches will be too loose.
2. If you must interrupt a Kitchener sequence (say, to answer the doorbell or the phone or a spouse or a child—you know what is most likely to break your concentration), don't leave off until both stitches on a particular needle, front or back, have been worked. So, your front needle's "knit off, purl on" should be an indivisible package, as should your back needle's "purl off, knit on." Keeping to that rule will make it much easier to pick up again at the right place.
3. If you're working with a very soft yarn, consider threading your tapestry needle with an accompanying strand of thread. This will help keep the really soft yarn from fraying to pieces. Later, when the Kitchener row is finished, you can go back and pick the thread out.