If you have not run the Wizard after the installation,I strongly recommend that you do so as soon as possible. Without completing the Wizard, your protection might be unnecessary high (some applications might not work due to Firewall restricting rules).
Also, it is advisable to run the Wizard upon each major configuration change in your computer (a newly installed application etc.) to update the Firewall settings accordingly.
To launch the Wizard at any time:
1. Open AVG Main Screen.
2. Double-click the Firewall component.
3. Press the Configuration wizard button (at the bottom of the dialog).