I don't know that particular watch but generally, in bands that have
arrows like that, they use friction pins that push out in the direction
that the arrow points. They also usually supply a hole or pry point
that allows you purchase to push the pin out. This is not always easy
since they tend to plate the bands with the pins installed. Sometimes
you can push them out from the opposite side, sometimes you can't.
Depends on that particular design.