How do you make old biro's work?

There are many ways to make old biro's work.

The most used one is the "Keep-f**king-scratching-on-this-piece-of-paper" technique. The name says it all.

Another one is rubbing it in between your hands. This generates heat, which makes the ink inside the pen warmer and easier to flow.

Other people try blowing down the ink tube to try and push the ink through, they are of course idiots who don't realise that air can't escape through the other side so there is no real point in trying that.

By the end of this it's best that you just buy a new pen.