We've learned to put ours in a sturdy shoulder lock to prevent squirming, and hold them there for a while afterwards. They then exit affronted, with a Mighty Leap, and the drops stay on their napes. It makes it a 2-person job, but it's a lot easier.
The other tip is to make sure that the liquid is at room temperature and that they haven't got any nicks or scabs in the area you're applying it. Failure on either of those counts results in mutiny.
