We came across a number of people who are scared of putting their spinnakers up, because of the challenge of getting them down if the wind increases.
We have developed this technique, which seems to work well.
1) Always wear sailing gloves. The sock can race up pulling the thin sock rope through your hands at speed.
2) Pull in the tack-line so the tack is easy to reach from the bow.
3) We use a quick-release snap shackle on the tack line, and completely release the tack. Merely letting the tack-line out, or the sheet, sometimes leaves the kite with pressure in it, and a round-shouldered kite can be quite resistant to having a sock pulled over it. The brand we use is called Wichard. Another one is Tylaska. Conventional snap-shackles can't be relied on to release under load.