Here's where I started a year ago:

1.Read Shorewall's website (Quickstart Guides) and download the
configuration scripts that fits you e.g.
2.Edit the configuration scripts, especially the "zones," "policy" and
"rules" scripts.
3.Make sure you have physical access to the firewall box (in case your
configuration locks you out of a network connection).
4.Run "shorewall start" from root and read the messages.
5.Go back and read the forum at Shorewall for specific questions.

Also:
1. Keep a hardcopy of your network configuration
2. Check you hardware, cables, etc.

It works great for me.

Ohmster wrote:
> Peteris Krumins <pkruminsREMOVETHIS@inbox.lv> wrote in
> news:Xns93B020BF0D657whitesuneapollolv@130.133.1.4 :
>
>
>>Uh, if you do not want to mess with firewalling, what's the point of
>>help then? Someone can tell you how to do it, but you wont be able to
>>react quickly if something happens. Then you will probaby ask again.
>
>
> Hmmmm, yes, I will do all of that when time permits. As it is, I have an
> open system with no firewall and that is the reason for the urgency to get
> a firewall running. I was hoping that someone with a similar setup could
> pass on the configs in order to get it running. Then I could tweak and tune
> it as I understand it better. Webmin seems like a good front end to do this
> with.
>
> Ask again? If I don't understand something and need some assistance I sure
> will ask more questions. My payback is to help others with situations that
> I have already dealt with and I do that all the time. iptables is not
> something that one gets a handle on right away, or at least that is the way
> it seems to me.
>
> Your advice and analogies are good though. :P
>