How do you add links to a watch band?

You have to get a needle and a small hammer. You first cut the point of the needle off, and then you place the needle on the end of the pin holding the links together. Once you have punched it completely out add the links needed and add a little oil (cooking oil is fine) to the pin and tap it back in with the hammer.

To add to this, it is best to hold the watch steady in a vice or something similar, but put a soft cloth against the edges of the vice to avoid scratching your watch. Best advice would be to take it to the professionals, at your local jewellers, as not all watches are tap out pins.