From your Outlook you have to browse in same tab where you create your automatic replies and than click on rules:

This window will pop up, choose "Add rule"

In next tab you can setup some rules.

If you leave all fields empty, and you check only the "Forward" box, all messages will be forwarded.

Otherwise you can put some restrictions e.g. messages sent only from certain e-mail address or similar.

After you have clicked Yes, you will be back on previous tab, and you will see your rule, that will be active only when your out of office is On.

You can create different set of rules, based on your needs.