As requested
1 - work from the bottom of the zit, but not too far away for the squeeze. Don't work from the top because that won't work.
2 - You can tell if the pop will be good dependant on whether the visible pus is big or small and whether it's like an anthill or like a just mound. If you've got an "anthill", you have a very promising squirt.
3 - If it's a big flat mess of inside pus, which I always thought meant you have a lot of openings the pus wants out, sometimes squeezing just gives you a big puddle of oil that comes out with no breaking or bursting point. Not worth the pain.
More later
