I've been given a few peppers plants a few weeks ago, which I'm now trying to grow inside, on my sunnier window ledges. While trying to find out how to care for them, most advice I've found seems to indicate that I should "pinch out" the top when the plant is ~30 to 40cm tall (the tallest is current;y about 30cm now, so I'll need to do something with them soon).
I understand why we do this, and think I know approximately what I should be doing, but I'm a complete novice and have never tried to do this before, and would rather not accidentally kill them early on.
So, exactly how do I pinch out a pepper plant?