You can use the program gwsetup. In this case, you just has to
launch this program (if your installation have not already
automatically started it), then open the (local) Web address which it
proposes and follow the instructions. The use is very simple and is
therefore recommended to the beginners.
Otherwise, if you have some knowledge about computers, you can
use commands in an interactive window. This use allows you to know all
the details of the commands and understand what happens, but is not
recommended if you are not a specialist of this kind of
approach. Click here to start this way.