Is there a specific timing for applying blemish patches?

Whenever I get acne, I always put on a blemish patch; some go down well, while others seem to last longer.

I am also confused about whether it is right to apply it to acne that hasn't opened yet, or to apply it after extraction.

I also feel like my skin gets more stuffy if I leave the patch on for too long. For those of you who use acne patches effectively, when do you usually apply them? Are there times when it's better to just leave them alone rather than use a patch?