I never done shocks on my Getz but I doubt it will be any different from any other small car. The procedure generally goes something like :
Put a jack under the bottom of the shocker and jack it up just a little.
Remove the top shocker securing nut (I think there are access panels on the boot trims of the Getz you remove to access the top mounting).
Remove the lower shocker securing bolt.
Lower the jack a little until the shocker clears the lower mounting then lower the shocker out of the top mounting.
Refit in reverse order.