In order to remove the links to shorten watch bracelet, you will require a special gadget which can be purchased from many of the online watch specialists.
If you google 'Watch band pin remover', you should get some idea of how to proceed, but basically, the pins you can see are split pins and must be removed in the direction of the arrow. Once the pin has started to protrude, a pair of pliers will easily remove it.
When replacing the pins, care must be taken to insert the pin back in the link the same way as it came out, ie. against the direction of the arrow.
It really depends on how confident you are with hand/eye co-ordination as to how successful you will be.
I adapted a bicycle chain link remover which, after a bit of tweaking did a fine job.
Alro, October 2006