[FYI, the "I" in this story is not me. The author wanted to share this info without being identified. Can you blame him? :) ]
I looked online and it's hard to find direct, simple instructions, they tend to get academic or theoretical about it.
It's very simple: APPLY HARD PRESSURE!
Once, I cut myself on the job trying to free a piece of metal, and got smacked in the forehead with the metal piece, and it was flowing pretty steadily. I got a paper towel and applied hard pressure for about 15 minutes and it stopped bleeding.
Another time, I dropped a ceramic bowl, it broke, bounced in the air, and the edge landed on top of my foot, right on a vein. It was practically a gusher and I had visions of bleeding to death like Stephen Foster. I did the same procedure and after about an hour, it stopped so I could steri-strip and bandage it. No stitches needed, although a doctor would have probably insisted.
A few weeks ago I developed a large skin tag on the side of my nose, real sightly! It was gradually drying out and it seemed safe to snip it off with a scissors. But it was not as dried as I thought and it started flowing pretty steadily from a small hole, not like a scrape or tear where 2 sides of the skin could fuse together. But I applied hard pressure for about an hour and it stopped.
So this is good advice for anyone who has kids or lives alone.